USB-Audio regression on behringer UMC404HD

[Takashi Iwai]

On Tue, 03 Jan 2023 16:14:57 +0100,
Michael Ralston wrote:
> 
> On Wed, 4 Jan 2023 at 02:13, Takashi Iwai <tiwai at suse.de> wrote:
> >
> > That's weird.  Is snd_usb_audio driver bound with the device at all?
> > That is, does it appear in /proc/asound/cards?
> >
> 
> Yes, it's there.
> 
> 0 [V49            ]: USB-Audio - V49
>                      Alesis V49 at usb-0000:08:00.1-3, full speed
> 1 [NVidia         ]: HDA-Intel - HDA NVidia
>                      HDA NVidia at 0xfc080000 irq 154
> 2 [U192k          ]: USB-Audio - UMC404HD 192k
>                      BEHRINGER UMC404HD 192k at usb-0000:08:00.1-4, high speed
> 3 [Generic        ]: HDA-Intel - HD-Audio Generic
>                      HD-Audio Generic at 0xfca00000 irq 156

Hrm...  Try to reload snd_usb_audio module with the dyndbg=+p option,
e.g.

  # modprobe -r snd-usb-audio
  # modprobe snd_usb_audio dyndbg=+p
  
Or you can try to put your own debug printk(); we need to make sure
whether it's really the right code you're testing at first.


Takashi