I got my new lcx 17m put on my boat and on my first trip to the river I was having problems. The GPS worked fine but the sonar sucked, false depth readings and complete screen clutter. Then I realized what my problem was. When I bought my boat it had a Garmin unit on it and when I launched my boat I reached up a turned them both on and they do not get along together. I don't need them both on but I thought when I was running I could go to full map on my Lowrance and sonar with the garmin. If I do I will have to turn the garmin off when I use the sonar mode on my Lowrance. Has anyone had similar problems? I can always get rid of the garmin or leave it there just for a back up, it does'nt hold a candle to my Lowrance.