I've used the playcenter so far without any hitches... The only probs I had in any recordings we my own fault (level too high/low on UA5), or problems with SBD (loose connection first time taping).
I have found that my transferred waves have a header issue with CDWave, but it hasn't caused any problems per se... I've always trimmed the front and back of my WAVs to give it nice clean edges anyways.
Sorry to hear folks have issues with their JB3s, mine been perfect so far (knock on wood!)
Terry