PS: I found Tonys' statement particularly prophetic.

The funny thing is, before the Mark2's came out, they did have all the synch bugs swatted. Synchs were rock solid for a while there. It's too bad to see these synch bugs getting reported now. For what it's worth, synchs have been very stable for me all this time, with all the revisions of the software since beta 10 or so.

By the way, your problem sounds a lot like what I experienced a couple times in the past: Errors on "rebuilding music database" that eventually self-corrected after enough synch attempts. Keep trying and see if it gets past it.

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Tony Fabris