Wierd Banding Issue - Atik 420c chip issue?

[akulapanam]

Attached is an example of one of the flats I took a couple of weeks ago because it shows the weird diagonal banding issue I'm getting with my light frames.

The flats do help remove the bands but I'm still getting some weird color cast and its not a complete fix.

I'm using the normal hyperstar with a IDAS filter screwed into it and a Atik 420c.

I have tried a couple of trouble shooting techniques and the diagonal banding definitely doesn't move with the led box position. It also appears on both flat frames and on individual subs of the deep sky object itself. The camera position is hard to test because on hyperstar the entire optical train rotates if you want to move the camera.

[akulapanam]

Well sure enough I checked my optics, CPC, Hyperstar, filter, and then camera for any source of the bands and...  upon examining the CCD chip in the light it appears to have slightly darkened areas that match the bands on the photo I attached.  What causes this issue?  I bought the camera in late April should I contact you or my dealer?