Pi 5 - sept 25th firmware - issues with USB disks

[bloke]

After updating the Pi 5 eeprom to latest

* CURRENT: Fri Sep 25 15:59:09 UTC 2026 (1790351949)

USB disk is behaving slowly and effecting system performance. Does not seem to effect nvme devices, just USB

reverting eeprom fixes issue
[code]# cd /usr/lib/firmware/raspberrypi/bootloader
[root@pi5 bootloader]# ls
backup beta critical default latest stable
[root@pi5 bootloader]# cd default/
[root@pi5 default]# ls
pieeprom-2026-05-26.bin pieeprom-2026-09-12.bin pieeprom-2026-09-25.bin recovery.bin
[root@pi5 default]# rpi-eeprom-update -f pieeprom-2026-05-26.bin
WARNING: flashrom not found. Setting RPI_EEPROM_IMMEDIATE_UPDATE to 0
*** CREATED UPDATE pieeprom-2026-05-26.bin ***

CURRENT: Fri Sep 25 15:59:09 UTC 2026 (1790351949)
UPDATE: Tue May 26 15:01:25 UTC 2026 (1779807685)
WARNING: Installing an older bootloader version.
Update the rpi-eeprom package to fetch the latest bootloader images.

Install bootloader 2026-05-26 over the current version (2026-09-25)? [y/N] y
BOOTFS: /boot
'/tmp/tmp.8VBZVJ8p3K' -> '/boot/pieeprom.upd'
Copying recovery.bin to /boot for EEPROM update

EEPROM updates pending. Please reboot to apply the update.
To cancel a pending update run "sudo rpi-eeprom-update -r".
[root@pi5 default]# reboot
[root@pi5 default]#
Connection to media closed by remote host.
Connection to media closed.[/code]


upstream issue is logged
[url]https://github.com/raspberrypi/rpi-eeprom/issues/899[/url]