Hi there,
I’m new to Unity, I’m doing the tutorials right now. I was doing the marble tutorial and I just wanted to put a sounf file to play during the game. I put an audio listener on the camera and an audio source on the platform. I imported just a small stereo loop in .wav (16bit, 44100) and set it on the audio source. I have the PlayOnAwake checked but I still cannot hear anything when I run the game.
What have I done wrong???
Is the sound mono or stereo? If it’s mono, I think it becomes spatial so maybe the camera is too far away to hear it?
It is stereo, and .wav (It wasn’t mp3!:))
and I also tried to move the camera near the platform (audio source) and still cannot hear any sound.
Well, I tried to put an audio source on the camera as well, but it didn’t work.
I started a new project and scene, created just a cube with an audio source and still didn’t work
I opened the fps tutorial that unity has from default and still I couldn’t hear any sound at all.
so, maybe is a hardware problem?
I’m running the trial version of Unity on a G5 at the University’s computers, cause my trial expired unexpectedly after the second launch.
the trial doesn’t support sounds?
(still haven’t recieved a serial to activate the trial version on my Laptop, just to be sure)
I saved a standalone version of the game and run it on my laptop. I can hear sound, so now I’m sure it was a hardware problem. 
I’ll ask for a technician tommorrow at the uni to check why this is happening. Anyway, thanx for the support. Great forum!!! 
Keep us posted as to how that shapes up and if any more help is needed. From what I read above it does seem hardware related on that machine though…
Did you try playing the audio file outside Unity? If it doesn’t work there, then its most probably some OS sound settings on the machine or hardware gone wrong.