I have installed Ubuntu Gutsy RC and I have the same problem in my two computers. It worked fine in both in feisty before. When I try to play music or video (using the default aplication, totem) for first time the codec installation program comes up and asks me if I want to install the codecs. I mark them all and install. After that I get sound (either movies or mp3's) but no image. I just see a some weird static image, like when you get bad reception on tv. The extrange thing is that you get a weird image when you play an mp3 as well, not the usual anymation you get in totem. Also listening to mp3 hanged my computer. The computer wasnt responsive at all, only the mouse was moving but cliking had no effect. I waited for 2 or 3 minutes and then rebooted.
When I rebooted, the codecs started working fine in both computers. Totem hasnt crash yet and everything seems fine. But a reboot was needed.
Also, in one computer I got the option to install three sets of codecs, while in the other I got only option to install 2 sets of codecs. "They Ugly set" was missing, though I have installed them fine from synaptic.
I dont know if its related or not, but in mythtv using the internal player, I can watch live tv with no problems but not videos at all. They wont load.
Ok. The mythtv isue seems to be gone now. Ill try to explain the situation as easy as I can:
-Installed mythtv and gstreamer codecs: Mythvideo wont even load the videos, and totem plays the audio but shows a static weird green image.
-First reboot.
-Totem seems to play everything fine, but mythvideo now loads the videos but only plays the audio. It shows the static weird green image.
-Second reboot.
-Everything seems to be playing fine.
I installed mythtv and mythvideo before I installed the gstreamer codecs. It seems like theres some kind of isue between them.