Bummer, I know! Really, tho- you'll have so much to be looking at and listening to- the crowd, other participants, people cheering you on. You won't miss it for the race! Don't worry.
I used to run with mine ALL the time, but in prep for my IM, I quit running with one, so I wouldn't get used to the music then dread the silence on race day. Weird thing- I actually like myself enough to be alone with my thoughts for hours on end. I didn't know I could take that much of me.

Enjoy the sounds of nature, other racers, spectators, and even your thighs rubbing together (it might make a calming, peaceful sound).
Have fun out there!!!!! I can't wait to hear all about it!!!