Updates Updates******
ABOUT NOISE DISTORTION - that suddently appears:
1. The problem with noise distortion did not get resolved connecting the iphone directly with the carplay box ==> hence the problem happens in wireless and wired mode
2. Rebooting the unit and/or the iphone and/or disconnecting the CarPlay dongle does not fix it.
3. Problem dissapears only after car was off for a while ==> the problem is with the control unit ... hold your thoughts for now
SOLUTION
As the units are USB OTG, i used an usb hub and put the carplay dongle and a external DAC: Soundquest Firefly Black 1.5. The DAC audio output goes into the radio using the cable i mentioned on item (1) on 1st post - I did removed the filter in the middle of the cable and changed pinouts
I use 3 usb connections now: Carplay dongle, Dragonfly DAC and USB remote with keyboard
The other USB goes into de glove box with a great remote: Wechip 2.4G Smart TV Wireless Keyboard Fly Mouse W1 from Amazon and that remote works great as an iDrive controller. Furthermore, brings up the volume up.
Note: After an android reboot the volume goes back to 10 and you have to use remote to bring up volume, only happens when you are using the Dragonfly DAC. Another solution for that will require another app, to change volume at boot time or/or rooting... investigating
FINAL STATUS:
- sound could not be better (but I need to go on long test drive)
- no noise distortion
REGARDING CONTROL UNIT:
This chinesse unit have 3 parts: Control unit, Bluetooth unit and Android unit (by either Rockchip of Snapdragon cpu). If you read the threads below you would understand clearly why using a Bluetooth OBD2 is not possible. The core of the unit is the Control Unit rather than the android module...
Read:
Bimmerpost:
https://f30.bimmerpost.com/forums/sh...6&goto=newpost
Github:
https://github.com/chinesebmwheaduni...nits.github.io
BimmerPost:
https://f30.bimmerpost.com/forums/sh....php?t=1500481
XDA Forum:
https://forum.xda-developers.com/and...eries-t3673558