Does a NPC starting to use an idle marker trigger some event? I've looked through the lists but I can't seem to find a likely candidate.

Also any tips on creating a new sound marker with custom sounds?

The flute music in game seems to be more like dialog than something like a door slamming so I was thinking a making a soundmarker with some recorded flute music that would be triggered by use of the playflute idle. But I need an event to be attached to the idle.