When Tony is pacing the lobby waiting for the phone call to tell him he got the job, his mark is visible. You can see the tape on the floor where he is supposed to stop and turn around. When they show him from a farther distance, the tape is gone.
Camera crew visible in mirrors during rehearsal segment.
When Tony is trying out for the second show, he is shown wearing number 46, but there is one quick shot of him wearing number 40, which was his number for the first tryout.