An acting audition is a job. You have to get that in your head. Doing well at an acting audition is the only way you will get the actual job and get paid. While you never know what you might be doing at an acting audition (especially a commercial audition) there are some things you should never do. These are things that may just get you blacklisted from a casting director so they’ll never call you in again. Try explaining that one to your agent.