This has happened to me 3 times. After the second repair, I was very careful not to plugin the camera with it or the computer turned on, but it happened again. The DVX100 1394 port is poorly made.
Anyway, Mack Camera informed me that they would not honor the warranty on the third repair and that it would cost me $525 for the part. They won’t charge labor, but the I would imagine that it would be around $200 for labor if they did, so you’re looking at around $700-$800 in repairs plus shipping.
I decided not to repair it and just buy a cheap Panasonic GS300 for my transfer needs. The bonus is that I can also use it as a backup b-roll cam, plus my wife can use it to tape the kids.
Moral of the story: follow everyone’s advice and don’t use your DVX100 for transfer. Buy an inexpensive panasonic mini-dv for that. Also, make sure you never hot swap. It’s not worth the risk.