View Full Version : [ubuntu] Intermittent (but frequent) media problems

September 23rd, 2008, 05:36 PM
Hello folks,

I'm having some issues with Ubuntu that have been going on now for some time. Frequently (but not all the time - that makes it fun, huh?) I can't play certain media files - either in my browser or in another application. For example, I cannot play MP3s right now, but I was able to play them early yesterday morning. I've tried multiple different applications (VLC, Amarok, RhythmBox, etc) and I've also tried to play them directly in the Firefox web browser - no luck.
Another example is .mov files on the web. I can see the movie play, but I hear no sound. Again, this doesn't happen all the time - sometimes it works, sometimes it doesn't.
In both cases, it appears as if the audio is playing - the track progress bar is moving... but nothing is coming out. I know it's not an issue with my hardware because other types of media work 100% of the time - such as youtube videos.

I have the 'restricted file format' for mp3s downloaded and installed, so that's not the issue.

Can anyone help me debug what is going on? This is getting rather annoying as I do like to listen to music on my computer a lot!


September 23rd, 2008, 10:03 PM
The obvious comes to mind.
Check to see that main and/or PCM are not muted.
I find on my MythTV slave, sometimes simply watching a recoreded program mutes PCM. Unmute and all is well.
Might have been watching (and listening to) mpegs and avis all night but one visit to Myth mutes it.

September 23rd, 2008, 10:51 PM
If you are using flash9, that will cause this problem more than anything else. You need libflashsupport installed to fix that. The most likely problem is that you have System/Preferences/Sound set to autodetect. You should change it to ALSA.

For a more extensive fix, you can read my guide here:


September 23rd, 2008, 11:28 PM
Thanks for the tips! Nothing was muted, but I did change my Sound preferences to select ALSA and installed the libflashsupport package - I'll see how it works.