I just had an idea: to use something like the speed control on youtube to slow down a song in order to practice the choreo. I'm not into choreography on skates yet. Back in "the day" (in dancing) we didn't have digital playback that could change frequency (BPM) without weirding out the pitch. I found an app for Mac called PitchNSpeed. Simple and free. I just tried it and voila. I'll probably use it when I get to skate-dancing. Let me know if this is news to anyone and a good idea.