Sound not working in SL

I can hear sounds in other applicaitons, play music in iTunes, play wav files, etc on my laptop, but recently all sounds in SL have stopped playing for me.

I don't believe in asking for help until I have exhausted all of my own resources, So...I searched the Knowledge base for sound issues, found nothing helpful. I read the Help files regarding preference settings. I triple checked all preferences, do not have mute audio checked, all volume control sliders are at mid point, my volume control on my computer is set to its highest level. But still I cannot hear any sounds in SL. No music, no user interface sounds, no sound effects like walking, no wind, I can not hear wav files that I tell to play, but my partner can.

I cleared the cache in preferences and deleted my cache file.

I reinstalled Second Life after deleting in and all library files.

I double checked this all a bit ago when no packet loss was showing, still no sound.

Does anyone have any idea what could cause this or how to fix it?

Computer: Mac PowerBook G4, 1.67 GHz PowerPC G4, 1.5 GB SDRAM, Mac OS 10.3.9

Can you hear anything in the real world?

I do believe that his first sentence started with "I can hear", right? Sheesh.

Yes I can hear sounds from all other applications in my computer, just not SL.