when receiving on channel 14 i have a high pitch tone coming in while someone is talking. this only happens on 14 .i have tried different mikes, checked swr ,soldering joints, grounds.this radio has never been worked on and still looks news.I could live with this high pitch tone but channel 14 is our call channel and its no getting rid of this unless you turn back the squelch or the rf gain to the point you can not hear.I hope someone may have dealt with this problem and have a solution to this. i forgot to mention this it happens on my base antenna as well as my wilson mobile antenna.