anyone have a 4000 may be able to help me. I just bought this unit and am a beginner. My 4000 just locks up, the Target ID may show any value from 40 to 80, and the category will show anything. Also the depth will show and me locked. It just locks up and stays that way for 30 sec. to 2 min. I can move over anything or point to the sky it stays froze. The battery hot. Somebody help me// my buddy bought a White's at a garage sale for $75.00 and is kicking my butt