
Hardware Requirements:
What we are building:
It uses the current ESP32-A2DP and Arduino Audio Tools approach. ESP32-A2DP receives SBC audio as 16-bit stereo PCM, and Audio Tools provides the I²S output layer.
In Arduino IDE → Library Manager, install:
Select an original ESP32 board, such as ESP32 Dev Module. The ESP32-S3 and C3 are unsuitable because they do not support Bluetooth Classic A2DP.


| PCM5102A | ESP32 |
|---|---|
| BCK | GPIO 26 |
| LCK, LRCK or WS | GPIO 25 |
| DIN | GPIO 22 |
| GND | GND |
| VIN | 5 V |
If exposed:
FMT → GND for standard I²SXSMT → 3.3 V for unmuted operationSCK → GND on the common PLL-equipped modulesThese pin assignments correspond to the established ESP32-A2DP PCM5102 setup.