That does not sound like the J & M I have dealt with. I am not sure what the electrical connection is you refer to. But would think propably the antenna cable that is one of the BMW antenna parts (which at that time was probably supplied to BMW by J & M). Or it may be an antenna ground wire. Either of which should be simple fixes.
I do understand J & M and BMW are not or have not been on the best of terms for a while since BMW changed suppiliers. But would think J & M and particularly John Lazzeroni would be of assistance on one of their own products and especially to their customers. They were of great help to me on the helmet headset I got for my '06 LT. They do get testy re BMW and the VOICE systems.
I suggest you call them and tell them the model etc on your cb, how long you have had it, the problem, and if possible avoid telling them it is on a BMW or at least tell them that after they have had a chance to respond to the problem. And if neccessary that it has nothing to do with the VOICE comm system. Here is the contact info I have used.
John Lazzeroni, J&M Corporation President [email protected]
Phone Toll Free in U.S and Canada
Outside the U.S.A. 1-520-624-7000
FAX (24 hour) 1-520-624-6202
1415 South Cherry Avenue
Tucson, Arizona 85713-1997
Hope you get it straight.