Re: [REGRESSION] Audient EVO4 hardware volume control now requires quirk

[Sasha Levin <sashal@kernel.org>]

> I was able to work around the issue by adding extra modprobe config to
> my system, specifically the below:
>
> options snd_usb_audio quirk_flags=2708:0006:ignore_ctl_error
>
> Does this quirk need to be added to the snd_usb_audio module or is
> there an underlying fix somewhere else?

The likely cause is 87a6f2fa6e6c ("ALSA: usb-audio: Propagate write errors
in generic mixer put callbacks"). It is in 7.2 and was backported to 6.18.53
and 6.12.111. Before it, a failed SET_CUR in the mixer put callbacks was
ignored and userspace saw success. Now the error is returned unless
ignore_ctl_error is set, which is exactly what your workaround does. It is
the only functional change to sound/usb/mixer.c between 7.1.13 and 7.2.5.

Could you confirm by reverting just that commit on 7.2.y or 6.18.y and
testing without the quirk_flags option?

-- 
Thanks,
Sasha