i just bought a new imac. When I go to play an mp3 in itunes or quicktime and have no sound.I noticed the volume slider on both apps are on mute. So i moved them back to the right for full volume, I can here the sound but as soon as I let go of the slider it slides down to the left again thus muting the sound. I tried VLC player and it played it fine with no slider to adjust. How can I get this slider to stay to the right for 100% volume?

Just an update. I use the keyborad shortcut (Command up arrow)and my volume stays at 100% until my mouse pointer goes near it then it mutes itself again(on itunes) but on qucktime my mouse can't go near the actual player without muting it.

I'm sorry it's not much help to you but there are a couple of similar situations reported on Apple's own Discussions...one person reports the problem with iTunes, QT and Final Cut Pro but unfortunately there are no replies to either post.