[mythtv-users] Audio-problem

[Ragnar Kjørstad]

On Sun, Apr 27, 2003 at 05:48:55PM +0000, brad at youreshop.com wrote:
> Hello,
> 
> I have the same card as you and I had this problem too.
> 
> It turns out there are various "Capture" mixers with this card. Try
> cranking all of them up to 100% and then if you get sound, do one by one.

I've turned them all up to 100%, and still no sound.

And, since aplay /dev/dsp works, I would think that the mixer-settings
would have to be correct?

> For me it was something like Sigmatel Capture that did it.

I don't have anything named "Sigmatel Capture" or anything like it.

You're refering to the different mixer-settings inside "alsa-mixer" (or
whatever), right?

I have:
Sourround Digital Capture,
Wave Capture
Music Capture
Line LiveDrive Capture
IEC958 Coaxial Capture
IEC958 Optical Capture
OEC958 TTL Capture
Capture
AC97 Capture

And they're all at a 100%. (Allthough I think only "Capture" is
relevant?)



However, I've made a litte progress:

If I do:
1. load drivers
2. run aplay-test while running xawtv
3. start mythbackend
4. start mythfrontend, watch tv
5. stop mythfrontend
6. stop mythbackend
7. run aplay-test while running xawtv
8. rmmod rivatv
9. modprobe rivatv
10.run aplay-test while running xawtv

The "aplay-test" is successful in 2 and 10, but not in 7.
In other words, mythtv is changing some state in the rivatv driver that
not only prevents sound from working inside mythtv, but prevents sound
from working outside mythtv until the driver is unloaded.

Not even pass-through sound works after running mythtv.

It turns out that mythtv somehow changes the settings for the rivatv
mixer (/dev/mixer1) - after having run mythtv the volume is set to 73
for one channel and only 5 for the other (used to be 100/100). The
mixer-change appears to be done when I stop watching tv, so it doesn't
explain why the sound doesn't work inside mythtv - only why aplay
doesn't work after. Allthough it may be two seperate problems, maybe 
they're related?

I can't comprehend why mythtv is changing that setting - I haven't even
told mythtv that I have a mixer at /dev/mixer1!

Can anyone shed some light on this?

Thanks.



-- 
Ragnar Kjørstad