Well
I've got the same problem. Here's what I have tried and noticed.
Zune still restarts with these conditions.
1. Debunked Wifi question: Wifi on or off (physically going to Zune Settings and enable/disable wifi).
2. Debunked Static issue: In your pocket, or laying on a flat surface.
3. Debunked bad mp3 issue: Removing all contents via Zune software (not reformatted). Also used ripped mp3s from my collection of CD's that play fine in my iRivers.
4. Debunked corrupted or hidden files issue: Totally reformatted Zune - press back button + up on squircle, then press back, center, and right button while in restart mode. This will wipe out the Zune and force you to reload the latest firmware.
5. Debunked non-charged battery issue: Draining the battery until the Zune does not turn on, then recharging until the battery indicator turns green.
6. Debunked headphone issue: Still restarts without any headphones attached.
7. Debunked level of volume issue: Still restarts when volume is below 9. I had it at 2, as well as 15.
8. Debunked plugged in issue: Still restarts when plugged in via AC/Adapter and car charger.
The only thing left to debunk is faulty hardware or faulty firmware. I am exchanging my Zune for a new one (Yeay for 2 year warrantees from Best Buy). If it still happens, then it is not the hardware i.e. hard drive or electronincs, but a firmware issue. From my extensive research in other forums, I found that this happened before in the first gen Zunes around firmware release 1.3 or before.
And yes, I have called Zune Support India and even they suggested that I exchange the thing. I'll let you guys know as soon as I have my new Zune.
My Zune, My Life, My Mess . . . Now what?
Zune 80GB, UE Triple.fi
Vista Home Premium 64-bit