Hey,
Have been struggling with this fault for the last couple of months now and it's stopped me using bluetooth completely, so some ideas would be great!
I have a 2007 GTI, with a version R RNS 510 and a Kufatec Fiscon Basic Plus.
It's been going strong since fitted in 2015 and I have had 0 problems until now.
When connecting bluetooth, after a few minutes of use, it will cause the RNS to go very very slowly. Eventually, the RNS will hard reboot itself and the issue will repeat. Slow slow slow, reboot, slow slow slow reboot etc. Once it goes slow, a full reboot followed by disconnection of bluetooth from the phone is the only way to get it out of this cycle.
See here from 1mins 30sec in and you can see just how slow it is:
Youtube LinkIf you the phone's bluetooth is off, the issue never appears so that's how we've been rolling for a few months now.
I took the RNS out last week and disconnected and reconnected everything but with no change. All wires seemed in good condition and there was no obvious damage to the Fiscon or RNS. VCDS comes up with 0 error messages as well and the radio is coded correctly (I hadn't been near the thing with VCDS for months at that point!). The MFD is unaffected when the RNS is going slowly and can be controlled with MFSW with zero delay.
I'm really at a loss. Hadn't worked on the car in a very long time and it seems to have gone wrong by itself.
Any other things you'd try that may resolve it?
Thanks!