Hi all,
just a quick note - I used to occasionally experience the AV700 powering off within music playlists, either a created playlist or an album. After a few tracks, the unit would just power off.
Spoke to Archos Europe and they advised reformatting the drive and resynching with WMP10 to clear a potential file corruption problem. This appears to have worked.
Failing that they suggested getting the unit replaced by the retailer.