I have a Zumo hard wired to the bike and linked to an Autocom Active Plus rider system. The system used to work fine until I had a problem with the Zumo and had to send it off for repair. The unit was replaced and now the sound levels are far too quite. I can hardly hear the GPS instructions and the music on the SD card is way too quiet. Any ideas on what can be done to increase the sound. The volumes have been set to 100% 



