Plenty have tried and some have suceeded, here is ehsmaes' guide to making a bluetooth audio receiver, allowing you to hook up your R-Pi to your stereo and use your phone as the sound source.
The wish list:
R-Pi Bluetooth and Airplay audio receiver: I want to be able to stream Spotify and other audio sources from a phone to my stereo. We have both Android and iOS-devices in our household so both should work.
The receiver shall auto-pair and auto-trust phones trying to connect
There should be a synthesized voice connect announcement (This is new, I think. I haven't seen anyone else doing this).
There should be support for A2DP and A2CP profiles for meta data and playback control.
Stand-alone operation. No display required. No login and manual steps, i. e. just plug it in and use it.
Easy, predictable scripted install
This is what you need to complete this project:
- Raspberry Pi (B+ v2 or Pi 2)
- Bluez-compatible bluetooth 4.0 dongle
- 8GB MicroSD
- A good solid power source for the Raspberry Pi
- A keyboard and display for initial setup
- Optional: R-Pi compatible WiFi dongle, e. g. Realtek RTL8188CUS
A note on the Pi version. I have used a Pi 2 during installation since it saves time. Then I move the completed MicroSD to a B+ V2. Running this application on a Pi 2 is a bit of a waste of CPU cycles.
Read more at; http://www.instructables.com/id/Raspberry-Pi-BluetoothAirplay-Audio-Receiver-combo/?ALLSTEPS