Thick Black Line in Shallow Water

[Fishcakes101]

I have a DFF-1 and 2 12" MFD screens, one dedicated to the DFF-1
I have written about this previously but it has been happening again.
In shallow water the top of my screen has a large black area that obscures a large part of the screen. It seems to come and go. Mt transducer offset is set to 0 so I don't thing that is the problem. I'm also running on Auto dual screen. Sorry it's sideways Thank you for any advice
Thank you for any advice.

 

[Johnny Electron]

One at the top is your temp line as you have the temp gauge graph turned ON. The other one lower on the screen is your cursor cross hairs. Just move your cursor with the cursor buttons and see it move.