HDMI audio on Raspberry Pi 4 broken

[azzu]

I installed alarm on my Raspberry Pi 4 and tried all steps I could find to get HDMI audio working. It works perfectly fine on Raspbian without any special steps. Also, local 3.5mm output works on alarm. "omxplayer -o local" works.

On one HDMI device I own there was also actually output, but nothing to speak of: everything I tried just produced scrambled, screeching sound. So apparently some kind of output is happening, but nothing that could be interpreted by my devices. 2/3 devices just produced no sound when trying to play audio.

So I believe it is something to do with alarm. Now, I don't know much about linux, its kernel or alarm, so I don't know which package this actually belongs to. Apologies for this.

I've talked about this in #archlinux-arm on IRC and I've tried a bunch of things already, which I'll list here. First, some outputs of different commands:

$this->bbcode_second_pass_code('', '
$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA]
Subdevices: 7/7
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
card 0: ALSA [bcm2835 ALSA], device 1: bcm2835 IEC958/HDMI [bcm2835 IEC958/HDMI]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: ALSA [bcm2835 ALSA], device 2: bcm2835 IEC958/HDMI1 [bcm2835 IEC958/HDMI1]
Subdevices: 1/1
Subdevice #0: subdevice #0
')

$this->bbcode_second_pass_code('', '
$ aplay -L
null
Discard all samples (playback) or generate zero samples (capture)
jack
JACK Audio Connection Kit
pulse
PulseAudio Sound Server
default
Default ALSA Output (currently PulseAudio Sound Server)
sysdefault:CARD=ALSA
bcm2835 ALSA, bcm2835 ALSA
Default Audio Device
usbstream:CARD=ALSA
bcm2835 ALSA
USB Stream Output
')

$this->bbcode_second_pass_code('', '
$ dmesg
[ 0.000000] Booting Linux on physical CPU 0x0
[ 0.000000] Linux version 4.19.84-1-ARCH (builduser@leming) (gcc version 8.3.0 (GCC)) #1 SMP PREEMPT Thu Nov 21 00:52:06 UTC 2019
[ 0.000000] CPU: ARMv7 Processor [410fd083] revision 3 (ARMv7), cr=30c5383d
[ 0.000000] CPU: div instructions available: patching division code
[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, PIPT instruction cache
[ 0.000000] OF: fdt: Machine model: Raspberry Pi 4 Model B Rev 1.1
[ 0.000000] Memory policy: Data cache writealloc
[ 0.000000] cma: Reserved 64 MiB at 0x0000000038000000
[ 0.000000] On node 0 totalpages: 1015808
[ 0.000000] DMA zone: 1728 pages used for memmap
[ 0.000000] DMA zone: 0 pages reserved
[ 0.000000] DMA zone: 196608 pages, LIFO batch:63
[ 0.000000] HighMem zone: 819200 pages, LIFO batch:63
[ 0.000000] random: get_random_bytes called from start_kernel+0x8c/0x504 with crng_init=0
[ 0.000000] percpu: Embedded 17 pages/cpu s37388 r8192 d24052 u69632
[ 0.000000] pcpu-alloc: s37388 r8192 d24052 u69632 alloc=17*4096
[ 0.000000] pcpu-alloc: [0] 0 [0] 1 [0] 2 [0] 3
[ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 1014080
[ 0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=0 cma=64M bcm2708_fb.fbwidth=1184 bcm2708_fb.fbheight=624 bcm2708_fb.fbswap=1 smsc95xx.macaddr=DC:A6:32:23:7E:2D vc_mem.mem_base=0x3ec00000 vc_mem.mem_size=0x40000000 root=PARTUUID=f3d83422-01 rw rootwait console=ttyS0,115200 console=tty1 selinux=0 plymouth.enable=0 smsc95xx.turbo_mode=N dwc_otg.lpm_enable=0 kgdboc=ttyS0,115200 elevator=noop
[ 0.000000] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
[ 0.000000] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
[ 0.000000] Memory: 3934052K/4063232K available (12288K kernel code, 834K rwdata, 3028K rodata, 2048K init, 886K bss, 63644K reserved, 65536K cma-reserved, 3211264K highmem)
[ 0.000000] Virtual kernel memory layout:
vector : 0xffff0000 - 0xffff1000 ( 4 kB)
fixmap : 0xffc00000 - 0xfff00000 (3072 kB)
vmalloc : 0xf0800000 - 0xff800000 ( 240 MB)
lowmem : 0xc0000000 - 0xf0000000 ( 768 MB)
pkmap : 0xbfe00000 - 0xc0000000 ( 2 MB)
modules : 0xbf000000 - 0xbfe00000 ( 14 MB)
.text : 0x(ptrval) - 0x(ptrval) (14304 kB)
.init : 0x(ptrval) - 0x(ptrval) (2048 kB)
.data : 0x(ptrval) - 0x(ptrval) ( 835 kB)
.bss : 0x(ptrval) - 0x(ptrval) ( 887 kB)
[ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[ 0.000000] rcu: Preemptible hierarchical RCU implementation.
[ 0.000000] Tasks RCU enabled.
[ 0.000000] NR_IRQS: 16, nr_irqs: 16, preallocated irqs: 16
[ 0.000000] GIC: Using split EOI/Deactivate mode
[ 0.000000] arch_timer: cp15 timer(s) running at 54.00MHz (phys).
[ 0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0xc743ce346, max_idle_ns: 440795203123 ns
[ 0.000005] sched_clock: 56 bits at 54MHz, resolution 18ns, wraps every 4398046511102ns
[ 0.000021] Switching to timer-based delay loop, resolution 18ns
[ 0.000237] Console: colour dummy device 80x30
[ 0.000697] console [tty1] enabled
[ 0.000742] Calibrating delay loop (skipped), value calculated using timer frequency.. 108.00 BogoMIPS (lpj=540000)
[ 0.000780] pid_max: default: 32768 minimum: 301
[ 0.001020] Mount-cache hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.001051] Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.001781] CPU: Testing write buffer coherency: ok
[ 0.002134] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
[ 0.060019] Setting up static identity map for 0x200000 - 0x20003c
[ 0.080019] rcu: Hierarchical SRCU implementation.
[ 0.120069] smp: Bringing up secondary CPUs ...
[ 0.200495] CPU1: thread -1, cpu 1, socket 0, mpidr 80000001
[ 0.280569] CPU2: thread -1, cpu 2, socket 0, mpidr 80000002
[ 0.360666] CPU3: thread -1, cpu 3, socket 0, mpidr 80000003
[ 0.360779] smp: Brought up 1 node, 4 CPUs
[ 0.360839] SMP: Total of 4 processors activated (432.00 BogoMIPS).
[ 0.360858] CPU: All CPU(s) started in HYP mode.
[ 0.360876] CPU: Virtualization extensions available.
[ 0.361606] devtmpfs: initialized
[ 0.369484] VFP support v0.3: implementor 41 architecture 3 part 40 variant 8 rev 0
[ 0.369791] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
[ 0.369833] futex hash table entries: 1024 (order: 4, 65536 bytes)
[ 0.371438] xor: measuring software checksum speed
[ 0.470451] arm4regs : 1458.000 MB/sec
[ 0.570519] 8regs : 1111.200 MB/sec
[ 0.670586] 32regs : 1108.400 MB/sec
[ 0.770653] neon : 2297.600 MB/sec
[ 0.770672] xor: using function: neon (2297.600 MB/sec)
[ 0.770697] pinctrl core: initialized pinctrl subsystem
[ 0.771463] NET: Registered protocol family 16
[ 0.774039] DMA: preallocated 1024 KiB pool for atomic coherent allocations
[ 0.774447] audit: initializing netlink subsys (disabled)
[ 0.774651] audit: type=2000 audit(0.770:1): state=initialized audit_enabled=0 res=1
[ 0.775500] hw-breakpoint: found 5 (+1 reserved) breakpoint and 4 watchpoint registers.
[ 0.775529] hw-breakpoint: maximum watchpoint size is 8 bytes.
[ 0.775714] Serial: AMBA PL011 UART driver
[ 0.777652] bcm2835-mbox fe00b880.mailbox: mailbox enabled
[ 0.804071] cryptd: max_cpu_qlen set to 1000
[ 0.971078] raid6: int32x1 gen() 212 MB/s
[ 1.141042] raid6: int32x1 xor() 177 MB/s
[ 1.311268] raid6: int32x2 gen() 320 MB/s
[ 1.481214] raid6: int32x2 xor() 256 MB/s
[ 1.651402] raid6: int32x4 gen() 303 MB/s
[ 1.821518] raid6: int32x4 xor() 262 MB/s
[ 1.991666] raid6: int32x8 gen() 338 MB/s
[ 2.161802] raid6: int32x8 xor() 236 MB/s
[ 2.331919] raid6: neonx1 gen() 734 MB/s
[ 2.501987] raid6: neonx1 xor() 764 MB/s
[ 2.672134] raid6: neonx2 gen() 1122 MB/s
[ 2.842206] raid6: neonx2 xor() 1007 MB/s
[ 3.012352] raid6: neonx4 gen() 1132 MB/s
[ 3.182481] raid6: neonx4 xor() 912 MB/s
[ 3.352578] raid6: neonx8 gen() 1136 MB/s
[ 3.522717] raid6: neonx8 xor() 916 MB/s
[ 3.522736] raid6: using algorithm neonx8 gen() 1136 MB/s
[ 3.522755] raid6: .... xor() 916 MB/s, rmw enabled
[ 3.522773] raid6: using neon recovery algorithm
[ 3.523111] bcm2835-dma fe007000.dma: DMA legacy API manager at (ptrval), dmachans=0x1
[ 3.524598] vgaarb: loaded
[ 3.524979] SCSI subsystem initialized
[ 3.525160] usbcore: registered new interface driver usbfs
[ 3.525215] usbcore: registered new interface driver hub
[ 3.525329] usbcore: registered new device driver usb
[ 3.542765] raspberrypi-firmware soc:firmware: Attached to firmware from 2019-11-19 16:40, variant start
[ 3.552775] raspberrypi-firmware soc:firmware: Firmware hash is aeebba4c03968ede49097db077673eadc2888a22
[ 3.564146] clocksource: Switched to clocksource arch_sys_counter
[ 3.676955] VFS: Disk quotas dquot_6.6.0
[ 3.677038] VFS: Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
[ 3.677200] FS-Cache: Loaded
[ 3.677375] CacheFiles: Loaded
[ 3.684942] NET: Registered protocol family 2
[ 3.685541] tcp_listen_portaddr_hash hash table entries: 512 (order: 0, 6144 bytes)
[ 3.685581] TCP established hash table entries: 8192 (order: 3, 32768 bytes)
[ 3.685646] TCP bind hash table entries: 8192 (order: 4, 65536 bytes)
[ 3.685722] TCP: Hash tables configured (established 8192 bind 8192)
[ 3.685846] UDP hash table entries: 512 (order: 2, 16384 bytes)
[ 3.685887] UDP-Lite hash table entries: 512 (order: 2, 16384 bytes)
[ 3.686057] NET: Registered protocol family 1
[ 3.686529] RPC: Registered named UNIX socket transport module.
[ 3.686553] RPC: Registered udp transport module.
[ 3.686571] RPC: Registered tcp transport module.
[ 3.686589] RPC: Registered tcp NFSv4.1 backchannel transport module.
[ 3.686611] NET: Registered protocol family 44
[ 3.686634] PCI: CLS 0 bytes, default 64
[ 3.686814] Unpacking initramfs...
[ 4.127031] Freeing initrd memory: 6532K
[ 4.137455] Initialise system trusted keyrings
[ 4.137611] workingset: timestamp_bits=14 max_order=20 bucket_order=6
[ 4.145389] FS-Cache: Netfs 'nfs' registered for caching
[ 4.145842] NFS: Registering the id_resolver key type
[ 4.145881] Key type id_resolver registered
[ 4.145900] Key type id_legacy registered
[ 4.145928] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[ 4.146406] JFS: nTxBlock = 8192, nTxLock = 65536
[ 4.152078] SGI XFS with ACLs, security attributes, realtime, no debug enabled
[ 4.157955] async_tx: api initialized (async)
[ 4.157984] Key type asymmetric registered
[ 4.158003] Asymmetric key parser 'x509' registered
[ 4.158076] bounce: pool size: 64 pages
[ 4.158128] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 250)
[ 4.158287] io scheduler noop registered (default)
[ 4.158309] io scheduler deadline registered
[ 4.158458] io scheduler cfq registered
[ 4.158478] io scheduler mq-deadline registered
[ 4.158496] io scheduler kyber registered
[ 4.158703] io scheduler bfq registered
[ 4.204836] brcm-pcie fd500000.pcie: dmabounce: initialised - 32768 kB, threshold 0x00000000c0000000
[ 4.204878] brcm-pcie fd500000.pcie: could not get clock
[ 4.204934] brcm-pcie fd500000.pcie: host bridge /scb/pcie@7d500000 ranges:
[ 4.204976] brcm-pcie fd500000.pcie: MEM 0x600000000..0x603ffffff -> 0xf8000000
[ 4.274175] brcm-pcie fd500000.pcie: link up, 5.0 Gbps x1 (!SSC)
[ 4.274380] brcm-pcie fd500000.pcie: PCI host bridge to bus 0000:00
[ 4.274409] pci_bus 0000:00: root bus resource [bus 00-01]
[ 4.274436] pci_bus 0000:00: root bus resource [mem 0x600000000-0x603ffffff] (bus address [0xf8000000-0xfbffffff])
[ 4.274490] pci 0000:00:00.0: [14e4:2711] type 01 class 0x060400
[ 4.274582] pci 0000:00:00.0: PME# supported from D0 D3hot
[ 4.276786] PCI: bus0: Fast back to back transfers disabled
[ 4.276814] pci 0000:00:00.0: bridge configuration invalid ([bus 00-00]), reconfiguring
[ 4.276998] pci 0000:01:00.0: [1106:3483] type 00 class 0x0c0330
[ 4.277106] pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x00000fff 64bit]
[ 4.277376] pci 0000:01:00.0: PME# supported from D0 D3cold
[ 4.279603] PCI: bus1: Fast back to back transfers disabled
[ 4.279631] pci_bus 0000:01: busn_res: [bus 01] end is updated to 01
[ 4.279667] pci 0000:00:00.0: BAR 8: assigned [mem 0x600000000-0x6000fffff]
[ 4.279697] pci 0000:01:00.0: BAR 0: assigned [mem 0x600000000-0x600000fff 64bit]
[ 4.279775] pci 0000:00:00.0: PCI bridge to [bus 01]
[ 4.279800] pci 0000:00:00.0: bridge window [mem 0x600000000-0x6000fffff]
[ 4.279962] pcieport 0000:00:00.0: enabling device (0140 -> 0142)
[ 4.280115] pcieport 0000:00:00.0: Signaling PME with IRQ 51
[ 4.280251] pcieport 0000:00:00.0: AER enabled with IRQ 51
[ 4.280398] pci 0000:01:00.0: enabling device (0140 -> 0142)
[ 4.280794] bcm2708_fb soc:fb: FB found 1 display(s)
[ 4.296969] Console: switching to colour frame buffer device 148x39
[ 4.300817] bcm2708_fb soc:fb: Registered framebuffer for display 0, size 1184x624
[ 4.303100] vc-mem: phys_addr:0x00000000 mem_base=0x3ec00000 mem_size:0x40000000(1024 MiB)
[ 4.303587] vc-sm: Videocore shared memory driver
[ 4.303901] gpiomem-bcm2835 fe200000.gpiomem: Initialised: Registers at 0xfe200000
[ 4.313722] loop: module loaded
[ 4.315699] Loading iSCSI transport class v2.0-870.
[ 4.318395] libphy: Fixed MDIO Bus: probed
[ 4.320080] bcmgenet fd580000.genet: failed to get enet clock
[ 4.321489] bcmgenet fd580000.genet: GENET 5.0 EPHY: 0x0000
[ 4.322859] bcmgenet fd580000.genet: failed to get enet-wol clock
[ 4.324249] bcmgenet fd580000.genet: failed to get enet-eee clock
[ 4.325588] bcmgenet: Skipping UMAC reset
[ 4.327073] unimac-mdio unimac-mdio.-19: DMA mask not set
[ 4.344166] libphy: bcmgenet MII bus: probed
[ 4.390849] unimac-mdio unimac-mdio.-19: Broadcom UniMAC MDIO bus at 0x(ptrval)
[ 4.393112] usbcore: registered new interface driver lan78xx
[ 4.394516] usbcore: registered new interface driver ax88179_178a
[ 4.395881] usbcore: registered new interface driver smsc95xx
[ 4.397200] usbcore: registered new interface driver cdc_ncm
[ 4.398690] xhci_hcd 0000:01:00.0: xHCI Host Controller
[ 4.399944] xhci_hcd 0000:01:00.0: new USB bus registered, assigned bus number 1
[ 4.403212] xhci_hcd 0000:01:00.0: hcc params 0x002841eb hci version 0x100 quirks 0x0000001000000890
[ 4.404770] genirq: irq_chip Brcm_MSI did not update eff. affinity mask of irq 52
[ 4.406693] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002, bcdDevice= 4.19
[ 4.408016] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 4.409308] usb usb1: Product: xHCI Host Controller
[ 4.410595] usb usb1: Manufacturer: Linux 4.19.84-1-ARCH xhci-hcd
[ 4.411880] usb usb1: SerialNumber: 0000:01:00.0
[ 4.413587] hub 1-0:1.0: USB hub found
[ 4.414945] hub 1-0:1.0: 1 port detected
[ 4.416598] xhci_hcd 0000:01:00.0: xHCI Host Controller
[ 4.417864] xhci_hcd 0000:01:00.0: new USB bus registered, assigned bus number 2
[ 4.419134] xhci_hcd 0000:01:00.0: Host supports USB 3.0 SuperSpeed
[ 4.420658] usb usb2: New USB device found, idVendor=1d6b, idProduct=0003, bcdDevice= 4.19
[ 4.421951] usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 4.423218] usb usb2: Product: xHCI Host Controller
[ 4.424476] usb usb2: Manufacturer: Linux 4.19.84-1-ARCH xhci-hcd
[ 4.425704] usb usb2: SerialNumber: 0000:01:00.0
[ 4.427301] hub 2-0:1.0: USB hub found
[ 4.428544] hub 2-0:1.0: 4 ports detected
[ 4.430616] dwc_otg: version 3.00a 10-AUG-2012 (platform bus)
[ 4.431917] dwc_otg: FIQ enabled
[ 4.431924] dwc_otg: NAK holdoff enabled
[ 4.431931] dwc_otg: FIQ split-transaction FSM enabled
[ 4.431940] Module dwc_common_port init
[ 4.432125] usbcore: registered new interface driver uas
[ 4.433408] usbcore: registered new interface driver usb-storage
[ 4.434664] usbcore: registered new interface driver ums-alauda
[ 4.435898] usbcore: registered new interface driver ums-cypress
[ 4.437092] usbcore: registered new interface driver ums-datafab
[ 4.438258] usbcore: registered new interface driver ums_eneub6250
[ 4.439404] usbcore: registered new interface driver ums-freecom
[ 4.440531] usbcore: registered new interface driver ums-isd200
[ 4.441624] usbcore: registered new interface driver ums-jumpshot
[ 4.442716] usbcore: registered new interface driver ums-karma
[ 4.443801] usbcore: registered new interface driver ums-onetouch
[ 4.444927] usbcore: registered new interface driver ums-realtek
[ 4.445995] usbcore: registered new interface driver ums-sddr09
[ 4.447039] usbcore: registered new interface driver ums-sddr55
[ 4.448041] usbcore: registered new interface driver ums-usbat
[ 4.449271] mousedev: PS/2 mouse device common for all mice
[ 4.450985] bcm2835-wdt bcm2835-wdt: Broadcom BCM2835 watchdog timer
[ 4.452266] device-mapper: uevent: version 1.0.3
[ 4.453427] device-mapper: ioctl: 4.39.0-ioctl (2018-04-03) initialised: dm-devel@redhat.com
[ 4.454937] device-mapper: multipath round-robin: version 1.2.0 loaded
[ 4.455900] device-mapper: multipath queue-length: version 0.2.0 loaded
[ 4.456836] device-mapper: multipath service-time: version 0.3.0 loaded
[ 4.457766] device-mapper: raid: Loading target version 1.14.0
[ 4.459749] sdhci: Secure Digital Host Controller Interface driver
[ 4.460706] sdhci: Copyright(c) Pierre Ossman
[ 4.461939] mmc-bcm2835 fe300000.mmcnr: could not get clk, deferring probe
[ 4.463128] Error: Driver 'sdhost-bcm2835' is already registered, aborting...
[ 4.464084] sdhci-pltfm: SDHCI platform and OF driver helper
[ 4.469016] ledtrig-cpu: registered to indicate activity on CPUs
[ 4.469528] hidraw: raw HID events driver (C) Jiri Kosina
[ 4.470101] usbcore: registered new interface driver usbhid
[ 4.470552] usbhid: USB HID core driver
[ 4.471400] vchiq: vchiq_init_state: slot_zero = (ptrval), is_master = 0
[ 4.472828] [vc_sm_connected_init]: start
[ 4.480679] [vc_sm_connected_init]: end - returning 0
[ 4.481475] bcm2835_vc_sm_cma_probe: Videocore shared memory driver
[ 4.481960] [vc_sm_connected_init]: start
[ 4.482573] [vc_sm_connected_init]: installed successfully
[ 4.483216] Initializing XFRM netlink socket
[ 4.483734] NET: Registered protocol family 17
[ 4.484386] Key type dns_resolver registered
[ 4.485081] Registering SWP/SWPB emulation handler
[ 4.486790] registered taskstats version 1
[ 4.487720] Loading compiled-in X.509 certificates
[ 4.489409] Btrfs loaded, crc32c=crc32c-generic
[ 4.500764] Key type encrypted registered
[ 4.506462] uart-pl011 fe201000.serial: cts_event_workaround enabled
[ 4.507525] fe201000.serial: ttyAMA0 at MMIO 0xfe201000 (irq = 34, base_baud = 0) is a PL011 rev2
[ 4.513919] bcm2835-power bcm2835-power: Broadcom BCM2835 power domains driver
[ 4.515012] brcmstb_thermal fd5d2200.thermal: registered AVS TMON of-sensor driver
[ 4.516107] mmc-bcm2835 fe300000.mmcnr: mmc_debug:0 mmc_debug2:0
[ 4.516919] mmc-bcm2835 fe300000.mmcnr: DMA channel allocated
[ 4.543327] sdhci-iproc fe340000.emmc2: Linked as a consumer to regulator.1
[ 4.560096] mmc1: queuing unknown CIS tuple 0x80 (2 bytes)
[ 4.562684] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[ 4.565267] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[ 4.569036] mmc1: queuing unknown CIS tuple 0x80 (7 bytes)
[ 4.571556] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[ 4.574156] mmc0: SDHCI controller on fe340000.emmc2 [fe340000.emmc2] using ADMA
[ 4.576753] of_cfs_init
[ 4.577758] of_cfs_init: OK
[ 4.581053] Freeing unused kernel memory: 2048K
[ 4.582310] Run /init as init process
[ 4.610269] random: fast init done
[ 4.611898] mmc0: new high speed SDHC card at address e624
[ 4.613462] mmcblk0: mmc0:e624 SU32G 29.7 GiB
[ 4.618652] mmcblk0: p1 p2
[ 4.631912] mmc1: new high speed SDIO card at address 0001
[ 4.804519] usb 2-2: new SuperSpeed Gen 1 USB device number 2 using xhci_hcd
[ 4.845500] usb 2-2: New USB device found, idVendor=174c, idProduct=1153, bcdDevice= 0.01
[ 4.846324] usb 2-2: New USB device strings: Mfr=2, Product=3, SerialNumber=1
[ 4.847512] usb 2-2: Product: AS2115
[ 4.848675] usb 2-2: Manufacturer: ASMedia
[ 4.849831] usb 2-2: SerialNumber: 00000000000000000000
[ 4.868224] scsi host0: uas
[ 4.870550] scsi 0:0:0:0: Direct-Access ASMT 2115 0 PQ: 0 ANSI: 6
[ 4.872780] sd 0:0:0:0: [sda] 468862128 512-byte logical blocks: (240 GB/224 GiB)
[ 4.873640] sd 0:0:0:0: [sda] Write Protect is off
[ 4.874277] sd 0:0:0:0: [sda] Mode Sense: 43 00 00 00
[ 4.874696] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 4.875858] sd 0:0:0:0: [sda] Optimal transfer size 33553920 bytes
[ 4.994205] usb 1-1: new high-speed USB device number 2 using xhci_hcd
[ 5.059078] sda: sda1
[ 5.062944] sd 0:0:0:0: [sda] Attached SCSI disk
[ 5.176803] usb 1-1: New USB device found, idVendor=2109, idProduct=3431, bcdDevice= 4.20
[ 5.178026] usb 1-1: New USB device strings: Mfr=0, Product=1, SerialNumber=0
[ 5.179237] usb 1-1: Product: USB2.0 Hub
[ 5.182700] hub 1-1:1.0: USB hub found
[ 5.184281] hub 1-1:1.0: 4 ports detected
[ 5.699921] EXT4-fs (sda1): mounted filesystem with ordered data mode. Opts: (null)
[ 5.856135] systemd[1]: System time before build time, advancing clock.
[ 5.885468] NET: Registered protocol family 10
[ 5.906547] Segment Routing with IPv6
[ 5.921313] systemd[1]: systemd 243.162-2-arch running in system mode. (+PAM +AUDIT -SELINUX -IMA -APPARMOR +SMACK -SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ +LZ4 +SECCOMP +BLKID +ELFUTILS +KMOD +IDN2 -IDN +PCRE2 default-hierarchy=hybrid)
[ 5.923572] systemd[1]: Detected architecture arm.
[ 5.931798] systemd[1]: Set hostname to <pi-homeserver>.
[ 6.205892] random: systemd: uninitialized urandom read (16 bytes read)
[ 6.209812] systemd[1]: Created slice system-getty.slice.
[ 6.211994] random: systemd: uninitialized urandom read (16 bytes read)
[ 6.213708] systemd[1]: Created slice system-netctl.slice.
[ 6.216041] random: systemd: uninitialized urandom read (16 bytes read)
[ 6.217671] systemd[1]: Created slice User and Session Slice.
[ 6.219665] systemd[1]: Started Dispatch Password Requests to Console Directory Watch.
[ 6.221507] systemd[1]: Started Forward Password Requests to Wall Directory Watch.
[ 6.223670] systemd[1]: Set up automount Arbitrary Executable File Formats File System Automount Point.
[ 6.225594] systemd[1]: Reached target Local Encrypted Volumes.
[ 6.321932] snd_bcm2835: module is from the staging directory, the quality is unknown, you have been warned.
[ 6.324900] bcm2835_audio soc:audio: card created with 8 channels
[ 6.541555] audit: type=1130 audit(1574296187.669:2): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-udevd comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 6.575528] audit: type=1130 audit(1574296187.709:3): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-journald comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 6.598397] systemd-journald[223]: Received client request to flush runtime journal.
[ 6.604216] systemd-journald[223]: File /var/log/journal/6dab997c57b84cb6bb95da3e26cd8975/system.journal corrupted or uncleanly shut down, renaming and replacing.
[ 6.704102] audit: type=1130 audit(1574296187.829:4): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-networkd comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 6.725754] rpivid-mem feb00000.hevc-decoder: rpivid-hevcmem initialised: Registers at 0xfeb00000 length 0x0000ffff
[ 6.726905] rpivid-mem feb10000.rpivid-local-intc: rpivid-intcmem initialised: Registers at 0xfeb10000 length 0x00000fff
[ 6.728046] rpivid-mem feb20000.h264-decoder: rpivid-h264mem initialised: Registers at 0xfeb20000 length 0x0000ffff
[ 6.729288] rpivid-mem feb30000.vp9-decoder: rpivid-vp9mem initialised: Registers at 0xfeb30000 length 0x0000ffff
[ 6.743442] media: Linux media interface: v0.10
[ 6.751807] videodev: Linux video capture interface: v2.00
[ 6.762171] iproc-rng200 fe104000.rng: hwrng registered
[ 6.776271] audit: type=1130 audit(1574296187.909:5): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-journal-flush comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 6.794767] bcm2835_mmal_vchiq: module is from the staging directory, the quality is unknown, you have been warned.
[ 6.805396] bcm2835_v4l2: module is from the staging directory, the quality is unknown, you have been warned.
[ 6.818299] bcm2835_codec: module is from the staging directory, the quality is unknown, you have been warned.
[ 6.819278] bcmgenet: Skipping UMAC reset
[ 6.829167] bcm2835-codec bcm2835-codec: Device registered as /dev/video10
[ 6.830333] bcm2835-codec bcm2835-codec: Loaded V4L2 decode
[ 6.833883] bcm2835-codec bcm2835-codec: Device registered as /dev/video11
[ 6.835158] bcm2835-codec bcm2835-codec: Loaded V4L2 encode
[ 6.857060] bcm2835-codec bcm2835-codec: Device registered as /dev/video12
[ 6.858183] bcm2835-codec bcm2835-codec: Loaded V4L2 isp
[ 6.914436] bcmgenet fd580000.genet: configuring instance for external RGMII (no delay)
[ 6.915868] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 6.917384] cfg80211: Loading compiled-in X.509 certificates for regulatory database
[ 6.944199] cfg80211: Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7'
[ 6.972422] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43455-sdio for chip BCM4345/6
[ 6.975080] usbcore: registered new interface driver brcmfmac
[ 7.011878] Bluetooth: Core ver 2.22
[ 7.012902] NET: Registered protocol family 31
[ 7.013880] Bluetooth: HCI device and connection manager initialized
[ 7.015273] Bluetooth: HCI socket layer initialized
[ 7.016229] Bluetooth: L2CAP socket layer initialized
[ 7.017098] Bluetooth: SCO socket layer initialized
[ 7.020710] Bluetooth: Generic Bluetooth SDIO driver ver 0.1
[ 7.124349] audit: type=1130 audit(1574296188.259:6): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-rfkill comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 7.144716] random: crng init done
[ 7.145558] random: 7 urandom warning(s) missed due to ratelimiting
[ 7.171049] audit: type=1130 audit(1574296188.299:7): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-random-seed comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 7.468559] audit: type=1130 audit(1574296188.599:8): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=lvm2-monitor comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 7.492404] FAT-fs (mmcblk0p1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
[ 7.549320] audit: type=1130 audit(1574296188.679:9): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-tmpfiles-setup comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 7.597732] audit: type=1127 audit(1574296188.729:10): pid=277 uid=0 auid=4294967295 ses=4294967295 msg=' comm="systemd-update-utmp" exe="/usr/lib/systemd/systemd-update-utmp" hostname=? addr=? terminal=? res=success'
[ 7.601041] audit: type=1130 audit(1574296188.729:11): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=ldconfig comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 7.994264] bcmgenet fd580000.genet eth0: Link is Down
[ 9.105079] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43455-sdio for chip BCM4345/6
[ 9.119222] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM4345/6 wl0: Feb 27 2018 03:15:32 version 7.45.154 (r684107 CY) FWID 01-4fbe0b04
[ 9.312644] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
[ 9.313870] brcmfmac: power management disabled
[ 14.144571] kauditd_printk_skb: 7 callbacks suppressed
[ 14.144579] audit: type=1131 audit(1574354722.175:19): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-rfkill comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 14.772946] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[ 14.939616] audit: type=1130 audit(1574354722.965:20): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=netctl@wlan.conf comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 14.947150] audit: type=1130 audit(1574354722.975:21): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=sshd comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 14.972412] audit: type=1130 audit(1574354722.995:22): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-user-sessions comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[ 14.974583] 8021q: 802.1Q VLAN Support v1.8
[ 14.978947] audit: type=1130 audit(1574354723.005:23): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=getty@tty1 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
')

$this->bbcode_second_pass_code('', '
$ amixer
Simple mixer control 'PCM',0
Capabilities: pvolume pvolume-joined pswitch pswitch-joined
Playback channels: Mono
Limits: Playback -10239 - 400
Mono: Playback 0 [96%] [0.00dB] [on]
')

$this->bbcode_second_pass_code('', '$ amixer controls
numid=3,iface=MIXER,name='PCM Playback Route'
numid=2,iface=MIXER,name='PCM Playback Switch'
numid=1,iface=MIXER,name='PCM Playback Volume'
numid=5,iface=PCM,name='IEC958 Playback Con Mask'
numid=4,iface=PCM,name='IEC958 Playback Default'')

$this->bbcode_second_pass_code('', '$ amixer contents
numid=3,iface=MIXER,name='PCM Playback Route'
; type=INTEGER,access=rw------,values=1,min=0,max=3,step=0
: values=2
numid=2,iface=MIXER,name='PCM Playback Switch'
; type=BOOLEAN,access=rw------,values=1
: values=on
numid=1,iface=MIXER,name='PCM Playback Volume'
; type=INTEGER,access=rw---R--,values=1,min=-10239,max=400,step=0
: values=0
| dBscale-min=-102.39dB,step=0.01dB,mute=1
numid=5,iface=PCM,name='IEC958 Playback Con Mask'
; type=IEC958,access=r-------,values=1
: values=[AES0=0x02 AES1=0x00 AES2=0x00 AES3=0x00]
numid=4,iface=PCM,name='IEC958 Playback Default'
; type=IEC958,access=rw------,values=1
: values=[AES0=0x00 AES1=0x00 AES2=0x00 AES3=0x00]')

Now what I tried:


- Unmuting the channels
- Setting "amixer cset numid=3 2"
- adding "hdmi_drive=2", "hdmi_force_hotplug=1" and "hdmi_force_edid_audio=1" to /boot/config.txt
- Everything that has been suggested here and here
- "aplay -D ... /dev/urandom" with all devices, same with an actual .wav file
- "omxplayer ...", "omxplayer -o hdmi" and "omxplayer -o both" (the last of which actually produced sound through the analog headphone jack)

However I have no real idea what I could do apart from that. After days of searching, experimenting, asking for advice on different places, and others reporting their HDMI audio not working and then just ignoring it because local output works, I think this is a problem in the support of the Raspberry Pi 4 in alarm somewhere.

[lvml]

The "screeching sound" you hear is probably just "way over-amplified into clipping/distortion by default".

Try "omxplayer --vol -2100 ..." - that may attenuate the sound enough to make it sound normal.

What I am surprised with is that you, at all, see ALSA sound devices on a Pi 4.

While you see in "dmesg":
[ 6.321932] snd_bcm2835: module is from the staging directory, the quality is unknown, you have been warned.
[ 6.324900] bcm2835_audio soc:audio: card created with 8 channels
... the second line is not emitted when I boot, and consequentially no audio devices at all are available.

(omxplayer uses the weird, proprietary /dev/vhci directly for audio-output, not ALSA.)

I would be interested to know what is different in your Pi 4 setup that you see ALSA devices, at all.

[azzu]

Well, I installed ALSA & omxplayer for exactly that reason, to get & play sound.

Lowering the volume does nothing. There is no loud screeching sound, it's just completely distorted and garbled. 2/3 of my devices still play nothing at all, with the other one just that weird random sound.