I installed a BT 4.0 adapter (BCM94360CD) fully internally within the Mac Pro. Everything supports well (both in Boot Camp and Mac OS) as well as Continuity (El Capitan). The only problem is its not smooth. I have other laptops with BT4.0 capability and they work just fine on my desk. (my Mac Pro is just underneath my desk to the right). I am using Logitech MX Master and Bose Soundlink Mini. They keep getting disconnected every 5 seconds or so and it's really annoying. The only thing that blocks between my BT4.0 mouse/speaker and Mac Pro are pc speakers, wifi HP printer, Samsung monitor and Nvidia Shield. I turned off their Wifi as well but it's not any better. It looks like the only way for me to get my mouse/speaker working without any disconnection is by putting them right next to where the BT adapter is (on the bottom of my Mac Pro). But it shouldn't be like this. Would this adapter be faulty? I bought this on eBay but I want to know if I should've gotten an OSX Wifi model or something. I mean they should be the same thing. Or is there any app that I can check the BT signal to find out what/where my signal is getting killed? Thanks..