Audio is always played via the audio jack of the master FPP PI. There are two common implementations:
- Connecting a set of speakers, via an amplifier / mixer (for sound in the yard).
- Connecting an FM transmitter to the audio jack, which then broadcasts the audio on a nominated FM channel (and this is then supplemented with a “Tune to” sign informing visitors to tune their vehicle radio stations to this channel).
Tip: A variation is to use the FM transmitter to transmit to an amplifier which is set to receive the broadcast on the FM channel which then drives the speakers.
A remote FPP will not play an mp3. (By design), it will play an mp4 video file. It does not support synced audio on remotes, as since the remote is subject to time adjustments, playing audio on the remote would sound odd to listeners.