Well, I'm suprised no one sugested this, but why don't you take your mp3 cd to a local car audio shop and try it in one of their mp3 players.
If it works then you know something is screwy with your unit, if not then you may not be writing the cd's properly.

 

I know the cds I create are fine - I've made a number for my bro-in-law... I can play the mp3 cds I create in my pc as well... like I was saying before, the unit knows that there's a cd in it - it just doesn't seem to be reading it. When it's in there, it just counts up and when I try to forward to the next song, it just starts over at track #1 - all this with no audio.

 

If you've made sure that you have a known good cd full of mp3's, the Kenwood should play it no problem. There is no setting you need to set, just stick the disk in and it should go.

If not, then that HU probably needs service. Assuming it's still under it's factory warranty, don't bother going to Best Buy, it'll just take longer, as it sits at their store for a while, and then gets sent to a service centre, repaired, and sent back to Best Buy. Look in your local Yellow Pages for an authorized service centre in your town, and show them the Best Buy receipt. They should be able to do the warranty work without you having to go through Best Buy.