I just re-ran AVwizard to check the settings...everything seems to be in order. I do get sound playing videos, but going to youtube, I get all the silent-treamtent.
Do you guys have an idea on how to fix this?
How are you 'going to YouTube'?
First thing I would suggest, if this is on your Core, add your username to the audio group in the /etc/groups file. It is a known issue that sound doesn't work under the default user, only under root, after lmce installs. This *may* be the issue you are experiencing here.
J.