I've updated my Airport Exrpress firmware to 7.3.2, and updated iTunes to 8.0.1(11). I was initially getting and firewall incompatability message, but that was solved by dumping the Firewall Switch widget I had installed. When the track won't play, I can get it to play by starting it over again with the iTunes "reverse" button. Can also get it to play by switching the iTunes output to my iMac's speakers, and then switching back to the Airport Express. I've tried switching channels on the router, resetting the router, resetting the Airport Express.... still same issue. I can't recall what prompted this, but if I recall correctly, it was when I updated iTunes a few days ago. I've checked permissions on my hard drive, repaired the hard drive, and ran a program called OnyX to "clean things up". Still same issue. The only thing I haven't done is do a "hard reset" on the Airport Express to get it back to factory settings, but am a bit leery about trying this. Would appreciate any suggestion you expert-level Mac users may have. Thanks.