I know this is an old thread. I have the same problem. I do not use the CB and I had similar issues. The only item on the radio that would work was the volume. It has lasted for weeks. I have had it to the dealer (under warranty) and they have split the fairing and did the dielectric grease and it works for a while the problem returns. When I have the problem and turn off the bike and start it again it does not fix the problem. One time it was not working and I was going to the dealership and on the way it started working OK.
This last fall I had it at the dealership and they mentioned if it happened again they would change out the module. This was last fall before I but the 07 Venture to bed for the winter.
Now the dealership closed so now I have to try and work with a new dealer.
Hope your problem gets fixed and it stays fixed.