Hey my Passat cousins, I need your help. I have a 2012 GLI with the Fender audio system and swapped my RNS 315 for an RNS 510. Everything is working flawlessly except the volume, I don't have any. I assume it has something to do with the external amplifier and it probably just needs to be coded. Does anyone know how I can get my volume to work and how to code this thing properly. Has anyone swapped the 315 for the 510 in the Fender system with any success. Thanks in advance, Peter.