Dragonfly 6 Sonar/DV blank

I recently installed a Dragonfly 6 with Navionics onto my Renegade Nomad 18 (shallow water center console). I love the gps features, but have been having problems with the sonar and down vision going to a blank screen after about 20 minutes of use. Sometimes I can turn the unit off and power it back up and itll be good for a while before going blank again. When it goes blank the depth often skyrockets as well. I recently updated to v12.09 hoping to resolve the issue, without any improvement.

Any suggestions would be great

Thank you

Robbie