A couple of things...
1. Create an invisible box around the button and convert it into a movie clip. That increases the hit rate, so you don't just have to click on the triangles... you can instead click around the triangles.
2. It was all good untill I saw the ending!!! You didn't stream your music, did you... Naughty Naghty! If you want something synchronized, you gotta stream it.
Perhaps we can have a colab sometime... Untill then...
Seeya!
P.S. Everything else was perfect!