I know this reply may be coming too late but I would like to comment that I had an identical problem with my 383L and I noticed the shutter was intermittently failing to close properly, leaving a narrow opening at the bottom that widened to leave an open triangular wedge in a corner through which if I shone a torch I could even see part of the circuit board.I phoned up Atik and sent off an email with a jpg showing the shutter ajar and they asked to have it back for repairs as it was still under guarantee.
I am waiting for it to be returned, hopefully with the shutter behaving as it should. I have read of others having a similar problem with this camera which is otherwise excellent gear. So it seems to be something it is prone to.