Having two Play Persistent Audio modules in Niagara will only play the first sound

Only one Play Persistent Audio module will work at a time in a Niagara emitter.

1. Create a new Niagara system with an empty emitter
2. Add a spawn rate module to the emitter's update script stage and set the spawn rate to 1.0
3. Add a play persistent audio module to the particle update script and set the Sound to Play to an easily discernable sound
4. Add an update persistent audio module to the particle update script with the same sound to play
5. repeat 3 and 4 with a new sound
6. Add the Niagara system to a level

RESULT

Only the first sound will play. Disabling or swapping the order of the Play Persistent Audio modules will change the sound that's played. Compare to the Play Audio module where multiple modules can play multiple sounds.