Bug 208851 - Steinberg UR22C: Crackling Audio
Summary: Steinberg UR22C: Crackling Audio
Status: RESOLVED CODE_FIX
Alias: None
Product: Drivers
Classification: Unclassified
Component: Sound(ALSA) (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: Jaroslav Kysela
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2020-08-09 13:17 UTC by Joshua Sivec
Modified: 2020-12-08 12:59 UTC (History)
1 user (show)

See Also:
Kernel Version: 5.8.0+
Subsystem:
Regression: No
Bisected commit-id:

Attachments
alsa-info.sh output (45.08 KB, text/plain)
2020-08-09 13:17 UTC, Joshua Sivec 		Details
Add implicit feedback quirk (522 bytes, patch)
2020-08-09 13:33 UTC, Joshua Sivec 		Details | Diff
Add an attachment (proposed patch, testcase, etc.)

Description Joshua Sivec 2020-08-09 13:17:08 UTC 
Created attachment 290811 [details]
alsa-info.sh output

The UR22C produces a crackling / pop noise once every while.

speaker-test -t sine at 48kHz produces one once every ~35 second.

It seems to require a implicit feedback quirk in /sounds/usb/pcm.c, lsusb -v -d 0499:172f also shows "Implicit feedback Data".

I simply added the following patch to the MOTU M & SSL2, since they have the same endpoint, this fixes the crackling / pop issue:

    case USB_ID(0x31e9, 0x0002): /* Solid State Logic SSL2+ */
+   case USB_ID(0x0499, 0x172f): /* Steinberg UR22C */
    case USB_ID(0x0d9a, 0x00df): /* RTX6001 */


However, duplex audio is not working with Pulseaudio anymore, similar to bug 207023. Jack works fine in duplex mode.

- Attached is the output of alsa-info.sh before the patch was applied.
- BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=207023
Comment 1 Joshua Sivec 2020-08-09 13:33:39 UTC 
Created attachment 290813 [details]
Add implicit feedback quirk

Attached is the patch, which simply adds the implicit feedback quirk (same as in the main post).
Comment 2 Takashi Iwai 2020-12-08 12:59:07 UTC 
The fix was merged in 5.9 kernel.
Note You need to log in before you can comment on or make changes to this bug.