I'm having problems with the thermal on my M2EA ... It displays only un-usable distorted images (see attachment).  It previously used to do it for a few minutes and then it would fix itself.  I assumed it was just the camera "aclimatizing" or something... but now I've gone through a whole battery waiting for it to correct, and it's stuck.  I''ve done FFC and it doesn't help.  

Any help or similar experiences please.

Yeah there's an issue which you aren't going to be able to fix yourself here. I would guess that there is a data cable issue, you'll need to submit a support ticket to DJI and get a replacement unit.