[mythtv-users] audio problems

[Michael T. Dean]

On 06/27/2006 03:36 PM, Chico Makani wrote:
> I'm running Myth 0.19 on Ubuntu Dapper. I have OSS and ALSA drivers 
> installed.

I hope you mean you have ALSA drivers installed and have also loaded the 
ALSA OSS emulation modules...

> mplayer works with either driver. I have an Nvidia4 chipset and 
> RealTek audio chip.
>
> If I run myth with the OSS driver device: /dev/dsp mixer: /dev/mixer
> I get audio but can't change the volume. If I open the mixer I can see 
> that there's a PCM-2 conrol that Myth is automatically setting to 100%.

Myth can only control Master or PCM controls on the mixer.  If your card 
uses a different name, Myth can't control volume for you.

> So I tried the ALSA driver. device: ALSA:default, mixer: default
> in this case I get no audio at all. From the log files it appears that 
> Myth is looking for a Master control on the mixer that does not exist. 
> Here's the message:
>
> 2006-06-26 14:20:20.137 mixer unable to find control Master

In frontend settings, under General settings on page Audio:

Mixer Controls
Changing the volume adjusts the selected mixer.

If you need to control something besides PCM or Mixer, you'll have to 
disable Myth's internal volume control:

Use internal volume controls
MythTV can control the PCM and master mixer volume.  If you prefer to 
use an external mixer program, then disable this option.

and use a script like 
http://www.gossamer-threads.com/lists/mythtv/users/192833#192833 .

Mike