I’ve tested starting 9 event instances at the same time but it did not prevent any other events from playing.
Could you let me know what the playSFX() function is doing? Could you also check your FMOD Studio project to see if you have any “max instances” on the buses or events in question? Please also take a look for any error messages in the console or debug logger of your game engine.
Ah yes, it looks like your music track was going virtual for some reason. Setting the priority to be higher than the sfx will ensure this won’t happen again.
The “Off” stealing behaviour means that any existing instances won’t be forcibly removed. It will wait until an event instance has naturally stopped playing before it will allow any new instances to be created/started.