I recently bought a 20" g5 imac. It has os x 10.3.7 on it
with all the updates. In the beginning all the audio
worked, but now only the audio works in things like itunes
and other media players like windows media player works,
as well system alerts work to and changing the volume
does produce sounds. Things like msn alert sounds when
new messeges are received, video streaming audio and
virtual pc sound no longer work. If this is any help virtual
pc says it is unable to access the mac audio system. I
only had the computer for about 2 weeks, if any one
knows a fix to the problem, maybe a setting or
something, I would be very happy to hear it. Thanks in
advance.

Your computer will still be under warranty. Call Apple and use your warranty phone support. This may be a common problem.

I also have the same problem with a G5 iMac bought in
January.

I say have because I phoned the Apple support people
here in Japan and the only solution they could
recommend was to reinstall the system. Which I did and
that solved the problem for about a week.

However, it has occured again a couple of times since
then. I've stripped off a couple of applications
(RadioShark and Omnioutliner Pro) which I Initially thought
may have been related to the problem, but it has just now
occured again.

Were Apple in the USA able to provide any solution which
doesn't involve re-installation of the system?