Problem:Cobra 139 xlr with digi-400

[Coyoteman]

Okay I have this cobra 139XLR with digi-400 connected to it when I transmit on the other radio it squeals really bad if I turn my dynamike down to almost 0 and my clarifier counterclockwise all the way it sounds alright I can turn the clarifier up to about the 10 o'clock position if that and it starts to squeal now if I go to the 12 o'clock position or more cuts out nothing after that there's no sound. Or if I leave my clarifier counterclockwise all the way and start pumping up my dynamike it doesn't take much nothing pass 9 o'clock position and it's just over power and if I keep going to this goes in the squealing feedback and all that stuff. It receives fine but I notice on lower sideband or upper sideband my clarifier has to be like at the 8 o'clock or less position for people to sound normal I go to 12 or beyond I get nothing. Does anybody have any idea what's wrong. Thanks