I’m using BK8000L Bluetooth module (SBC audio decoding performance) and as amplifier the PAM8403  board. (but you can use any other amplifier for example from you old PC speaker)

Problem with feedback and noise

If  we want to power the both devices from the same power supply, It will get a lot of noise. (ground loop noise)
To eliminate sound noise we should using separate power supply to drive the Bluetooth and amplifier.

Main component are:
– Bluetooth Stereo Audio Module Transmission BK8000L
– PAM8610 2x15W Amplifier Board Digital
– Power supply ca 7 to 9V for PAM8610 and 3.3v for Bluetooth
– Two speakers

For 3.3V power for BK8000L I used a simple USB/AC Adapter charger and with a AMS1117 Voltage regulator convert the 5 volt output to 3.3 volt. Keep in mind to added 100 uF and .1 uF capacitor between VCC and GND.

Recommend is to use a 100uF/25V electrolytic capacitors between VCC and GND.