Polo 6R - RNS510 and 9W7 Bluetooth

I installed the RCD510 and 9w7 Bluetooth module a year ago and had no issues where I coded it using vagcom. I thought to upgrade to the RNS510 this year, simply believing it would be an easy swap. Everything is working as it should, though when I connect Bluetooth I have no audio? It shows the songs playing and can change music and enter phone book, but there is no sound at all when using Bluetooth. Just before the swap, my RCD510 did not have this issue. I connected it back to vagcom but I can't see anything different that I must do. I've also updated my iPhone and tried others, restarted the radio etc. Any advice on this matter would be appreciated.