USB-Audio regression on behringer UMC404HD

[Takashi Iwai]

On Tue, 03 Jan 2023 20:29:54 +0100,
Michael Ralston wrote:
> 
> On Wed, 4 Jan 2023 at 06:27, Michael Ralston <michael at ralston.id.au> wrote:
> >
> > On Wed, 4 Jan 2023 at 06:24, Michael Ralston <michael at ralston.id.au> wrote:
> > >
> > > I did a diff between the sound/usb directory for 6.0.16 and 6.1.2 and
> > > reverted that entire directory.
> > >
> > > It is working with that change, so there must be something else.
> > >
> >
> > Logs below...
> >
> 
> This line from the logs stands out to me as different. Could this mean anything?
> 
> > Jan 04 06:20:27 leatherback kernel: usb 1-4: clock source 41 is not
> > valid, cannot use

This might be due to the commit
ac5e2fb425e1121ceef2b9d1b3ffccc195d55707
  ALSA: usb-audio: Drop superfluous interface setup at parsing

I believe it's time to check which commit broke things.
Assume that the bug is USB audio core changes, the following 8 commits
are relevant:

1045f5f1ff0751423aeb65648e5e1abd7a7a8672
9355b60e401d825590d37f04ea873c58efe9b7bf
a74f8d0aa902ca494676b79226e0b5a1747b81d4
9902b303b5ade208b58f0dd38a09831813582211
9a737e7f8b371e97eb649904276407cee2c9cf30
2be79d58645465351af5320eb14c70a94724c5ef
ac5e2fb425e1121ceef2b9d1b3ffccc195d55707


Could you try to revert from top to bottom one-by-one, and check which
one makes things working again?  The most suspected one is
2be79d586454 (one before the last, a big change), but who knows...


thanks,

Takashi