Thanks for the help, that picture really seemed like it would work. Really. I can't see any flaws in it. It's really clear and easy to see how it works. The trigger toggles the bottom two, m0 (cropped out of the 2d view, sorry) which goes to the second two, m1 and m2. m1 has the 'inactive' box checked. Both sides have an activator, targeting the other side's relay, a deactivator targeting its own relay, and a music file. Two possibilities attempted: 1. m1 targets the three entities titled music1. m2 targets the three entities named music2. Result: Each time I press the button, music2's file restarts. 2. m1 targets music1, and applies target2 and target3 to m1a and m1d. m2 has the same, but with music2, m2a, and m2d. Result: First press activates music2's music, every subsequent press does nothing. In the latter I switched the order of target2 and target3, thinking it was important whether it hit the deactivator or activator first, but there was no change. I've checked, re-checked, and re-re-checked all the targets and targetnames and entity types to make sure everything is in order.