This is a very common problem with the second generation Venture. The radio is actually located under the gas tank, the handlebar controls has a multiprong plug to connect it with the radio, this plug is located behind the front fairing in between the backing fairing(the black part on the inside) right at the top of the fork. This plug collects moisture from many sources and starts to corrode the connections, pull the plug apart and use a contact cleaner and a tiny stiff brush and clean the prongs on the plug. Then spray with WD40 and plug back together, then use rubber tape and cover the entire plug and make as waterproof as possible. This procedure made my 08 radio sound and work like new.