Linux RoonBridge with Bluetooth 5.0 USB Adapter to Sony WH-1000XM4

What I wanted to achieve:
A dedicated Linux Roon Endpoint for the Sony WH-1000XM4 without the need for an Android, Windows or iOS device.

I started with:

  • Mpow Bluetooth 5.0 USB dongle model: BH456A
  • Hardkernel Odroid HC1 runnning Armbian Ubuntu Hirsute Hippo unstable with kernel 5.13.8

To make it work I had to:

  • Download bluetooth firmware and copy it to the right place.
  • Compile LDAC codec from source.
  • Compile Bluezalsa from source.
  • Re-compile the kernel, as the snd-aloop module was not available in the kernel.

Now Roon can play music to the loopback interface. With the alsaloop command you can then capture the sound from the other side of the loopback adapter and point it to bluealsa.

modprobe snd-aloop
alsaloop -C hw:Loopback,1 -P bluealsa -t 100000 -n -S 1