Bluetooth headset pairs but won't connect, not avail as playback devic

I just want to confirm that I have finaly solved this issue and the problem is definitely with the BT drivers. I had the exactly same situation (I was able to pair the headset, but could not make it to work). You probably have the generic BT drivers installed from Microsoft database (same as I had). The generic drivers have some issues and are not designed to work 100% with all functions. For example, i did not have any issues with transferring files from/to my mobile phone, but as soon as I tried to connect my headset I find out that there is a problem. So you need to uninstall the drivers and install the real one from the BT adapter manufacturer. If you are using laptop then download the driver from the official website for your laptop manufacturer/model.
But very important thing before you uninstall the generic drivers and install the real one, is that I strongly recommend to disable/disconnect any internet connection you have, since once you will uninstall the drivers, Windows will probably start to install them again from Microsoft update database.

So this is the step by step procedure:

1) Download the BT drivers from the official site of your BT adapter manufacturer, or from your laptop official download website.
2) Disconnect all internet connections.
3) Uninstall the generic BT drivers (reboot the system if windows is asking to do that)
4) Open device manager again to see if the BT drivers are uninstalled, if not uninstall them again.
5) Install the official BT drivers. After installation is complete, you can connect your PC to internet again.
6) You should be able to use your device now. Pair the headset, right click on the device, select services, and then click Listen to music. Enjoy the sound :)

I was FINALLY able to get this going with different drivers. I had to search around for something that matched the device profile and now it works. If anyone is interested, the Canyon CNR-BTU6 driver seems to work for a lot of those small usb BT plugs.