I have a 10" Excalibur II and used it about four times on the beach. I used it Thursday and it worked fine. This morning Saturday I went to the beach again and it is working except the volume on the headphones is very low. I checked the settings and the volume control. There just isn't enough volume in the headphones. By the waves its impossible to hear. Anyone experience this? I guess it has to go back to Minelabs. Doesn't seem to be a wire because it isn't intermittent its constant. Unit has never gotten wet except for the coil.