Just trying out this plugin on a test player. I use HDMI audio output for the production show, and while testing this on another player I have for testing purposes, which is running the latest FPP 9.3 and the latest version of this plugin, I can only get background sound and PSA to play from the sound blaster play 3. I can also launch a sequence with audio and it will play via HDMI at the same time the background music is still playing on the sound blaster. I can get no audio for PSA or background music to play through the onboard headphone jack or HDMI. The player settings are set to output via HDMI.
I also can only hear PSA if the background music is stopped.