On my 2004 SR 185 sport for the longest time I would occasionally hear a "chirp" or several "chirps" in a row, thinking it was my alarm on the engine. After talking to mercruiser and my local mercruiser dealer both people believe the chirps are coming from the depth sounder. The weird thing is I really only hear it when i'm cruising around for 5-10 minutes at 25mph or so, or when I've towed skiers or tubes. It definitely doesn't happen often but still kind of annoying. My depth sounder is a stock one from SR and the model is TFXIDD next to that there is a number not sure what it means but it is 7474678. The brand is Teleflex. Any help would great. Pictured is what it looks like.