The Bluetooth has a 6 pin plug on it.Similar to the RCI . Pin 5 and 6 operate the bluetooth features. Pin 1 is Ground, 2 is audio, 3 is transmit...
The Cobra 29 has been the Staple of truckers radios for decade. Simple Rugged, and has logged Billions of miles when compared to all the others....
Sounds to me like your antenna is tuned for the a & b bands. What you describe is not commonly known as a radio problem. You will need a antenna...