For those of us who use AVRCP BT headsets and want to use a audio program other than HTC's or WMP!
Go
here D/l the CAB, install and reset. I can confirm that both Coreplayer and Pocketplayer now work with my Plantronics 855/TP/MR5 setup. No longer does the pause button on the headset launch WMP. Finally, I'm back to the functionality of my old Mogul! The DLL is from a 6.5 build so I don't know if it will work with 6.1. I'll never understand why HTC tied the AVRCP controls with WMP in the first place, instead of leaving them alone. I hate WMP, so this has been one of my biggest peeves about the TP, good riddance!
Thanks to Da_G and Captain_Throwback!!!!