Right now grading takes a lot longer than it needs to. Here are my suggestions for speeding up the workflow.
1 - Don't load the backing track. Why is this necessary? It adds loading time and the only option you have is to listen to student recorded audio anyways.
2 - After grading, automatically move on to the next assignment. Why should I have to wait for the assignment I just graded to reload and then also have to click the next button?
3 - Why is there a button to start grading that opens up options? I'm on the page, obviously I want to grade. Get rid of that mouse click!