GitHub - pschatzmann/ESP32-A2DP: A Simple ESP32 Bluetooth A2DP Library (to implement a Music Receiver or Sender) that supports Arduino, PlatformIO and Espressif IDF
BLE 4.1 Bluetooth Transmitter Stereo Audio GFSK Wireless Low Energy
Arduino Bluetooth Audio Transmitter Module Manufacturers and Suppliers - Wholesale Products - FEASYCOM
Amazon.com: HiLetgo HC-05 Wireless Bluetooth RF Transceiver Master Slave Integrated Bluetooth Module 6 Pin Wireless Serial Port Communication BT Module for Arduino : Electronics
Motorcycle Bluetooth hub: 5 pin DIN to Arduino to Cardo bluetooth headset - Project Guidance - Arduino Forum
Bluetooth Transmitter – Chipset, Power, Datasheet and Uses - Hackster.io
Reverse Engineering Your Own Bluetooth Audio Module | Hackaday