Help with sounder problem. TZTL12F + 520-5MSD

[SVAscension]

I installed all of this new this February and it has been working great until a couple months ago. The sounder works well under 150’ depth and displays a bunch of junk in anything deeper. Both high and low freq has same problem. I have checked the sounder and it is clean, have even cleaned it with a sponge. See attached pic.

Any suggestions?

 

[Johnny Electron]

Bottom discrimination mode is On. I would turn OFF all the advanced features like BD, Accufush, and RezBoost to start off with as you troubleshoot. Please provide more photos at the working depths and then some beyond 150. That photos looks like noise but it is too hard to tell what is going on just from that one photo.