Chevy, I'm not one to question your pronouncements with regard to your own rom, but my bluetooth controls are definitely not working. In fact, they are not working in exactly the same way as in 4.7.
I am running 4.8 unthemed with the 1ghz kernel. My jawbone mono headset works fine--the single button does what it's supposed to. However, my Motorokr S9-HD stereo headset is not working correctly. The volume down button opens bluetooth voice dialing and the pause button skips tracks. The track back button as well as the volume up button work correctly. The other two buttons do nothing.
I know you said you troubleshot (troubleshooted?) the bluetooth controls using a motorokr. Is there something different in the unthemed version? Did I somehow get an old version of the relevant package?
Which apk controls the bluetooth controls so I can try replacing it from the .zip?