Dual Thunderbolt MacBook Retina Late 2013 Audio + Brightness issue

[waterchill]

Hi,



I have a problem with this setup. If I hook both display's daisychained or separately (doesn't matter) both displays will be recognized as one display. So both displays are working fine but in audio settings it appears only one "Display Audio" instead 2x "Display Audio". Also Brightness is only possible for one display. If pressing F1 or F2 sometimes it control display 1 or sometimes display 2 brightness. If pressing control + F1 the brightness logo appears on other display (display 2) but the brightness is still control on display 1. Display slider is for both in settings menu but every slider works only for the same display. Also audio comes out from display 1 or 2 every restart the macbook or replug the thunderbolt cable.

If running Photobooth, i can switch between the 2 cameras fine. This is working.

This problem as far as i remember I have since 10.10 and with 10.11. I remember that before 10.10 it worked fine.

I tried:

PRAM reset
SMC reset
Deleted com.apple.windowserver.plist

Nothing helped.

Any ideas? Thank you.