First things first.
Newgrounds.com/downloads
Left hand side, Flash Loaders
Add one to the first frame of your animation and then double click it
The time-line should be different, go to the first frame on the top layer that has an , " a " present.
Right click on this frame and on the drop-down menu go to actions
You should see something like this
_root.stop();
stop();
Below those lines add in stopAllSounds();
So it looks like this
_root.stop();
stop();
stopAllSounds();
This will prevent your animation from looping, Aaaaand more importantly the audio from looping.
Now on to the animation itself.
I find it hillarious how someone stabbed the microphone into the stage and to be honest, if this animation were set in the Newgrounds Portal itself it could be one massive satire on how much Newgrounds loves dick jokes.
That Literally every single person on the site is laughing their balls off at one guy simply coming out and stating, "Penis." It sounds like it would be a riot, may even get front page if pulled off properly.
Though other than that there isn't really much else to say other than the curiosity over what flashes at the top right side of the frame when the protagonist ( I say that lightly ) Steps from between the curtains.
I recommend story-boarding before you begin animating and submitting things that are more substantial to the Newgrounds Community, though since this is your first real Digitally produced piece ( I see your last animation was submitted and is a stop-motion on graph paper. Lots of ingenuity there and I actually quite liked it by the way. ) Noone is going to be suspecting something over the top down-right insanely glorious from you:
And I in-fact really appreciate you submitting this work for me to view though again, the basic polish needs to be shown before we can truly begin admiring your creative side to full extent. Don't worry though I'm sure when you've more experienced you'll have alot more to show us : D
I'll be watching for your next few animations friend!
Have a nice day. :)