Bug 112773
| Summary: | 'Fuzzy'' sound issue with via82xx / alc650 under Fedora Core 1 - both with Standard and ALSA drivers | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Aimery de Malet <aimery_demalet> |
| Component: | kernel | Assignee: | Arjan van de Ven <arjanv> |
| Status: | CLOSED WONTFIX | QA Contact: | Brian Brock <bbrock> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 1 | CC: | noa, rdieter |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | athlon | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2004-09-29 19:54:35 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
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Description
Aimery de Malet
2003-12-31 05:59:19 UTC
I suppose this is the same probelm that I encountered (however, the description fuzzy is a bit fuzzy). Does the problem go away when resampling the example to 48khz? To test this do the following: 1) Grab a cd (preferrably a soft one) and rip a track with 'cdparanoia -X TRACKNUM' 2) play the resulting wav file with 'play cdda.wav' and verify that the audio problem exist 3) use the following command line to resample the track to 48khz: sox cdda.wav -r 48000 cdda48.wav polyphase 4) now play the resulting wav file with 'play cdda48.wav' and here if the problem is gone My guess is that the hardware only supports 48khz, but the drivers emulates support for 44.1khz (cd rate). Some drivers does this better (xp, oss) than others (alsa) at the moment. I'll try to investigate this further myself, but "fixes from above" would be appreciated. ps. my hardware as reported by lspci: VIA Technologies, Inc. VT8233/A/8235/8237 AC97 Audio Controller (rev 50) Firstly I think that the sound artefact is better described as 'sizzling sound' when playing 44.1khz audio. After some poking around in the ALSA jungle I found that the DXS autodetection doesn't work properly (It is my understanding that DXS is the ability to mix different sounds in hardware instead of just doing software mixing) DXS behaviour in alsa is controlled by the dxs_support parameter that can be sent to the snd_via82xx module when loaded. If I set dxs_support to 0 or 1 I get broken 44.1khz audio, however if I set the parameter parameter to 2, 3 or 4 the problem is gone. One thing that made this a lot more difficult to debug is the fact that /etc/modprobe.conf contains the following line: install snd-via82xx /sbin/modprobe --ignore-install snd-via82xx && /usr/sbin/alsactl restore >/dev/null 2>&1 || : A line that effectively and silently 'eats' all parameters sent to the snd-via82xx module as additional modprobe arguments. Could this be fixed in some better way? According to http://alsa.opensrc.org/index.php?page=via8233 the autodetection that is supposed to happen by default is done by a list of known good hardware i in the kernel, a list that apparently needs to be updated. I'll notify upstream about this for my particular hardware (An ASUS A7V8X motherboard with integrated VIA 8235 sound.) Others might want to do the same for their hardware if they also have this problem problem. In the meantime I can work around the problem by adding the line 'options snd-via82xx dxs_support=4' to my /etc/modprobe.conf According to https://bugtrack.alsa-project.org/alsa-bug/bug_view_page.php?bug_id=0000284 this issue is supposedly fixed upstream in alsa now for my particular hardware. Same problem, Fedora Core 2, latest errara kernel. FC2's stock kernel worked fine. Thanks for the bug report. However, Red Hat no longer maintains this version of the product. Please upgrade to the latest version and open a new bug if the problem persists. The Fedora Legacy project (http://fedoralegacy.org/) maintains some older releases, and if you believe this bug is interesting to them, please report the problem in the bug tracker at: http://bugzilla.fedora.us/ |