[mythtv-users] Slow video, Max CPU, bad sound

David Peach mailinglists at dpeach.com
Thu Jan 15 10:10:31 EST 2004

Thanks for the reply. I mentioned that I got ALSA turned off and OSS only.
That is what was locking everything up. When I went back to ALSA I got my
(play for a couple of seconds and then pause) video and static back.

> 1) Try a different sound or video player and see if you get sound.

When I use XawTV, it works fine. I have to unmute the line in of the sound
card though. In MythTV, MythMusic works just fine, either from a ripped CD
or one in the tray.

> 2) What your player here is trying to do is use Alsa's legacy OSS support
> which you may not have enabled. You might instead want to switch to
> /dev/adsp (which is alsa's primary device).

In one place of the Setup it let me choose /dev/adsp. In mythtvsetup it
only had /dev/dsp and /dev/sound/dsp. I manually changed it to /dev/adsp
but that did not change anything. When I went back to mythtvsetup it was
gone and back to /dev/dsp.

> 3) If this doesn't work, you can check to see if the alsa modules loaded
> by typing lsmod on the command prompt. You are looking for things like
> snd-yursoundmodule, snd-pcm, snd-pcm-oss (for the backwards compatability
> to oss). If your module and pcm are not both loaded, it will not work at
> all.

My sound module is snd-via82xx. Here is the sound information from the
snd-seq-oss            32000   0  (unused)
snd-seq-midi-event      6080   0  [snd-seq-oss]
snd-seq                42544   2  [snd-seq-oss snd-seq-midi-event]
snd-pcm-oss            43652   0
snd-mixer-oss          14200   0  [snd-pcm-oss]
snd-via82xx            15360   0
snd-pcm                79588   0  [snd-pcm-oss snd-via82xx]
snd-timer              18436   0  [snd-seq snd-pcm]
snd-ac97-codec         45720   0  [snd-via82xx]
snd-mpu401-uart         4704   0  [snd-via82xx]
snd-rawmidi            17760   0  [snd-mpu401-uart]
snd-seq-device          5832   0  [snd-seq-oss snd-seq snd-rawmidi]
snd-page-alloc          9044   0  [snd-via82xx snd-pcm]
snd                    41380   0  [snd-seq-oss snd-seq-midi-event snd-seq
snd-pcm-oss snd-mixer-oss snd-via82xx snd-pcm snd-timer snd-ac97-codec
snd-mpu401-uart snd-rawmidi snd-seq-device]
soundcore               6340   0  [snd bttv]

> 4) If it looks like its playing but you can't hear anything (might even be
> the case even though it gives you the error message you stated), its
> probably because you never unmuted the alsa outputs.

I hear plenty of static. I did not mute/unmute anything in alsamixer. All
the changes I have made with mixer settings has been through KMix as per
the MythTV documentation.

Am I right to assume that my problem is mostly related to sound? I
understand that it has much to do with MythTV's performance.

Thanks again.


>>> I was getting no sound except loud static. This was while using the
>>> /dev/dsp as my sound device. But as I read on the list here when using
>>> ALSA (which I believe I am since it is loaded in my Services Manager of
>>> Mandrake) to add an entry into my mysql database for "ALSA:hw:0,0". I
>>> have
>>> also chosen that as my sound device in mythtvsetup and mythfrontend
>>> Settings. Now I get no sound at all.
>> I have now gotten OSS working (I think) and ALSA turned off (I know).
>> But
>> this is what I get now:
>> Opening OSS audio device '/dev/dsp'.
>> player: Can't open audio device: /dev/dsp
>> Along with this, mythTV just completely hangs and I have to do a Cntl-C
>> from the command line to stop the frontend.
>> I am running the via82cxxx_audio driver for my VT8233 [AC97 Audio
>> Controller] on board sound. This is an MSI K7T266 Pro motherboard.

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