[Brian]

We've gotten some info from another developer that appears to explain what's going on here. Bonjour actually tries to find your sync server using both the WiFi and Bluetooth radios. That traffic, combined with the sync traffic, can cause radio interference.

We've got a lead on a way to work around this, but for the time being, folks experiencing this should be able to work around the issue by turning Bluetooth off for the duration of their sync. Sorry for the inconvenience this causes!