This past weekend, my new Lowrance Elite 7 Chirp started showing a really snowy picture on both the sonar and DI. I haven't added anything new or changed settings from 2 weeks ago when it was crystal clear. I was however trolling in <8' of water most of the time. I tried adjusting sensitivity setting and it got a little better but it still had snowy vertical lines, making it hard to see some of the fish I was marking. Any idea if the shallow water with all the pollen could be the problem? My new helix 5 on the front of the boat was crystal clear. I don't recall seeing this issue when we were shrimping in 4-5' of water last fall.

Any suggestions would be appreciated.