I have a RPi Zero W running Stretch and equipped with an Adafruit speaker bonnet. I have followed these instructions including points 1 and 2 mentioned in the comments. The result is a functioning BT speaker system so long as the sender is an iOS or Android device.
I would like to use the setup with another RPi; however, I am running into problems. I have two RPi 3B setups, one is running stretch, the other buster. On stretch, I have been able to pair the RPi Zero W speakers and they function properly when using a command such as:
aplay -D bluealsa:HCI=hci0,DEV=<BTADDRESS>,PROFILE=a2dp test.wav
However, despite successful pairing and setting the BT speakers as the output device in the Audio menu of the desktop GUI, I cannot get sound from youtube videos in chromium. With the buster setup, I can pair the device; however there is a timeout when attempting to set the RPi Zero W as the audio output. There's also something wrong with my buster setup as I am unable to perform the
aplay command above.
I am looking for instructions on how to successfully send sound from a recent RPi distro (stretch/buster) to another RPi serving as a BT speaker receiver. I would also like some clarification on whether pulseaudio, alsa, or both are needed in order for this configuration to run properly.