View Full Version : 0.21 fixes + Karmic = Sound Problems

November 20th, 2009, 11:35 PM
I've been using Ubuntu for about 2 years now with SVN compiled of MythTV with special patches. I've never had any problems under Feisty though Jaunty.

A few days ago I updated the box to Karmic as I always do every 6 months. I had to recompile my Myth source and reinstall it of course.

This time I'm having major problems with the sound. It basically doesn't work and the video goes choppy, sometimes I'll have small spurts of broken audio come through. I've tried changing the audio output from ALSA:pulse to ALSA:default and all the other ones. I've tried setting environment variables related to pulse such as PULSE_INTERNAL, PULSE_EXPERIMENTAL...., etc... I checked my .asound.rc file for the mapping of default to pulse. I've tried all the tricks with pasuspender, padsp, aoss. Nothing works. I get tons of "prebuffering pause" messages and messages about the audio buffer depending if I run the frontend with -v audio and so forth. I've done a lot of searching before posting here and it seems I'm the only one with this problem.

The only thing I've noticed to make any difference is while I have the frontend open, if I make changes in the gnome-volume-manager app from "stereo duplex" to any of the other choices it kind of makes the Myth sound go crazy choppy. The other strange thing is that although Myth is silent I still see a volume slider for it in the Pulseaudio volume control.

Very strange. I'd appreciate any tips and would like to know if there are any Karmic users out there running 0.21 fixes.

December 1st, 2009, 07:04 PM
I figured this out on my own, it was a PEBKAC. The problem was that I was declaring "v4l2-ctl -b off" in my mythbackend init script. Apparenly the 1.4.1 version of ivtv module doesn't like this anymore and causes the audio/video to go out of whack.