[alsa-devel] snd-usb-audio syncronisation problem

[Clemens Ladisch]

Adrian Stancu wrote:
> Using the original module, the momentary frequency is always stalled
> at 48000Hz during playback:
> vader:~# while sleep 0.3; do grep "Momentary freq"
> /proc/asound/card1/stream0; done
>     Momentary freq = 48000 Hz (0x6.0000)
>     Momentary freq = 48000 Hz (0x6.0000)
>     Momentary freq = 48000 Hz (0x6.0000)
>     Momentary freq = 48000 Hz (0x6.0000)
>     Momentary freq = 48000 Hz (0x6.0000)
>
>  note: I started playback after issuing the command.
> So maybe this particular type of interface does not report back
> correctly, thus confusing the driver?

This is possible.  Please try to put printk's into
retire_playback_sync_urb(_hs) to see whether these functions ever get
called, and whether the line "subs->freqm = f;" is reached.

Please show the entire contents of /proc/asound/card1/stream0 while the
device is playing.


Regards,
Clemens