It requires an isolated set of contacts that make momentarily.
I used the 50 volt signal that energized the targets in the gun game to energize 48v "ice cube " relays.
Relays like these can run $2 to $25 each and the base is another $5 each.
The WAV trigger has a ground strip ( buss) and 16 individual hot connections.
Making the a hot to the ground buss ( or any ground) will play that particular sound.
You cannot back feed it any voltage thru your switch source. So it needs a dedicated momentary switch.
On their website they have the programming manuals free.
They have other ways to trigger the sound but if you make contact too long it will play that sound effect stacked one on top of another.
I also had ghost triggers. I suspect it was the magnetic field from the coil closest to the board.
Earthen grounds and shielded wire did not cure this.