One other thing I noticed during testing; having a browser open caused issues with the song generation window. Not this problem specifically, but others like the stylepicker list coming up with a blank area, or hiding behind the main screen. With browser closed I had no problems. Just mentioning it.

I tried a bunch of times to duplicate the problem you are having (again just now) and couldn't get it to happen. I don't know what else to suggest.

My name is Bob by the way.. or rharv is fine, either way.
I'll sift through testing notes and see if I can find anyone else that had this issue, and post any results if I find them.

Do you have any tempo changes in your song by chance?

Make your sound your own!
.. I do not work here, but the benefits are still awesome