Is there a electical connection in the transmission.

Hello, The transmission will not have a connection for the radio, and the only connection I would make there is if the speedometer quit as well. You likely have a bad connection on the harness for the radio, and hitting the transmission tunnel is probably sending a vibration through the dash as well. My advice is to remove the radio, leave it connected, and manipulate the connector to the rear to see if you can make it turn off. You will have to hunt this one down, but the radio connectors for VW/Audi/Porsche are know for coming loose.