usb 1-1.1: Creating new data endpoint #88 usb 1-1.1: Creating new sync endpoint #84 usb 1-1.1: Creating new data endpoint #8 I have enabled kernel dyndbg, these are the outputs, hoping they are useful: > I forgot to add a quirk bit for controlling this, and it's changed only via
> Another thing you can try to set lowlatency=0 option for snd-usb-audio. (In reply to Takashi Iwai from comment #30) You've tested all quirk bits and nothing helped with respect to the stuttering bug, right? It's something else, and currently I have no idea yet. So the stuttering has nothing to do with the shared clock issue. > does not complain for the clock source. > The sad part is that audio stuttering is still present even if the kernel OTOH, my patch tries to reduce the unnecessary inquiry and setup of the clock when it's shared with multiple endpoints, hence it reached to the same end effect. > has the same effect without requiring the ref_counting.Īpparently the clock source error comes from some unstable response of the firmware of Behringer device, and adding delays seem helping for that. > It is strange however that adding the delay using: > as you were supposing the "clock source 41" error is not reported anymore. > I've tested the patch on 5.17, it is applied cleanly (all hunks succeeded) (In reply to Luca Russel from comment #27) I can do some debugging and test possible patches, but I need support to help. Just for the record, I experimented a bit with the current quirks available:Īny pointers/directions on how to solve this issue? With the new patched kernel module, the error on invalid clock source 41 disappeared, but the audio stuttering is still there. I also verified that this problem appears with recent version (bcdDevice=1.35) while does not occur with older firmware (bcdDevice<=1.12).Īnyway, I rebuilt the kernel patching the snd_usb_audio by adding a delay after commands (following the same quirks done on other interfaces for invalid clock source, like Teac for instance - see Bug 108961 – Teac UD-503: clock source 41 is not valid). "Clock Source 41 not valid" in syslog and during playback the audio starts and stop continually, it does stuttering. When the device is connected via USB (both 2.0 and 3.0 ports), I see Dell XPS with Ubuntu 20.04 on kernel 5.8. I have tested the Behringer UMC 404 HD usb audio device ( ) Output of alsa-info -no-upload for UMC202HD Quirk table entries for Behringer devices 5.15-v7l+, 5.8, 4.18 on both x86_64 and arm64Īlsa info from older model that is working without issue.īheringer UMC 404 HD bcdDevice=1.35 - LSUSB verbose - confirmed audio stutteringīheringer UMC 404 HD bcdDevice=1.35 - alsa-info - confirmed audio stutteringīehringer UMC 204 HD bcdDevice=1.35 - alsa-info.sh - stutteringĪ workaround patch for interface reset at clock change
0 kommentar(er)
