Remove the cable and squeeze the connectors onto the cable again (or put them in a vice to do the same - not too tight!) then re-fit the cable to the unit and sync again.

Okay, I took the cable out and it looks like that might be the problem, one of the ends is a little loose. I squeezed the cable end with all of my might and it didn't seem to help. It's the end on the first drive, which is the one complaining about the lost interrupt. I think I'm just going to have to order a new cable.

Does anyone know of an online store that I could purchase one from?

One thing to note though, it always starts giving me the time errors at the same spot in the sync (see attached picture). I don't know if that is significant or not.