I have tried to make a Bluetooth speaker with raspberry Pi three months ago. It was failed because of the old Bluetooth 2.0 USB device. It is too slow to get the smooth audio transferring.
Now I have a new Bluetooth 4.0 USB dongle.
I checked the information from the terminal window.
The procedure of installation is same as the post I posted before.
The dongle I got is $2.99 each. Good price. After I tested it, I can say Good quality.
At DX.com http://www.dx.com/p/ultra-mini-bluetooth-csr-4-0-usb-dongle-adapter-black-143276#.WQ_KC8ZlC70