The squelch needs to be turned all the way off before it works? Is that true on all the WX channels also? Does it sound clear when it does receive? Do people respond to a "radio check" request on a common channel (68)? How old is it?
It's possible that the internal squelch circuitry has malfunctioned. A rare occurrence but possible. That would leave three options:
1. Buy a new radio.
2. Contact the factory to inquire about repair.
3. Keep it as-is for emergency use.
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"Knot Easy" 2000 Horizon 240 Volvo 5.7GS /SX
tow: 2017 Honda PILOT EXL-AWD
prev. boats:
'87 Chaparral 198CXL 4.3 OMC Cobra
'69 Jetstar 16ft Ski Boat, 115hp Yamaha
'68 Aluminum Jon Boat, 3hp Sears
'64 Water Wings