DRMATTH - I don't often give (or take) advice - BUT if NOISES OFF is a show you have always wanted to do, don't miss a chance to audition for it. There is always time to watch DVD's later.
If you don't, when the show opens and when you see it, you will always wonder if you should have. And if you don't audition, you won't know. I know what you mean. From May-September I do four shows - doing various things, acting, directing, tech, choreography - and then the rest of the year and do two or three others.....if you want to do the show, audition.