Well error code c:31:30 might have smth. to do with humidity. The bad part is the cassette gets stuck. After taking out battery and trying to eject while off/on/camera/memory modes the device finally spits the cassette out in unusable shape. This happenned to me with a 4K memory sony cassette, with no memory tdk cassettes that i got from costco it did not happen yet (after 3-4 hours...)
This is with dcrtrv70
Note that I tried to call service they put me on hold for 50 mins. Online chat support sony.com/support could not help either and suggested me take the camcorder to service. It seems to work fine now...