VW Bluetooth kit whispering to me

[iichel]

Recently the telephone volume, voice command volume for phone and bluetooth streaming have been acting strange:

- Phone calls... not hearable
- Voice command volume very very low
- Bluetooth music only offers the left channel. But volume ok.

So i've checked:
- Phone bluetooth volume on phone (max), telephone volume on RNS510 (max)
- Adaptation of phone module, volume +10dB
- Phone settings for bluetooth music

All of this made no difference.

I have a RNS510 hardware 1T0 035 680 R coding 00000440010000810005
9W7 bluetooth from carsystems PL hardware 7P6 035 730 N coding 0210000000010110
MDI from carsystems PL hardware 5N0 035 342 G coding 020100

The strange thing is, it used to work properly but I've noticed last week that it is not working optimally.

[iichel]

So, the in-call volume is also affected in the same way.

I've learned that only left channel is normal since the right channel is not always wired.

Anyone know what to do?