Building a Bluetooth DAC with Raspberry Pi Zero W – Page Fault Blog
RASPIAUDIO – CHOOSE YOUR AUDIO HATS FOR RASPBERRY PI
Turn your old speakers or Hi-Fi into Bluetooth, Airplay and Spotify receivers with a Raspberry Pi and this step-by-step guide
Raspberry Pi Zero, audio output via I2S – lucadentella.it
tinyToslink - Raspberry Pi Optical Audio from Beni_Skate on Tindie
Amazon.com: Audio HAT Module for Raspberry Pi 4B/3B+/3B/2B/B+/A+/Zero/Zero W/Pi Zero WH,WM8960 Hi-Fi Sound Card HAT Stereo CODEC, Play/Record : Electronics