I experience the same problem, and have diagnosed extensively. Not certain if it does it with WiFi as well, but when Bluetooth is on it keeps scanning for other devices constantly. I have placed location on low (phone GPS only) and turned off both WiFi and Bluetooth scanning also in location and still have all kinds of trouble with my Bluetooth headset. In addition, when my phone is connected to one Bluetooth device and I turn another on there is a "hiccup" with the connected device.
So what /really/ needs to happen is for the programming to be updated so when connected to a Bluetooth device it stops scanning for other devices unless done manually.
So please Android, fix this soon, it is extremely frustrating to have my $200 Bluetooth headset cutting in and out while walking down the street when on the phone with someone or listening to music.