Ever since I hooked up my Logitech Z680 speakers using the optical out port I keep losing certain sounds out of my G5. For instance I'll be able to hear the Mail.app sounds, empty trash sounds, DragThing docking sounds, etc. However, after a sleep or even just after a while I'll get no sounds from those functions. However, iTunes, iChat, Final Cut Pro, QuickTime player, DVD player will play sounds just fine. This seems to happen even when I use System Preferences to switch to the internal speaker. This condition can be alleviated by a restart. But then deteriorates again.
What gives!?! Any ideas!?!