Audio can be a bitch. My first like 7 animations all lagged and had errors. Toke me almost 5 months to get it. Pretty much the key is to optimize it all and stream the audio. This tut. http://www.newgrounds.com/bbs/topic/4 65403 should help you.

How's the flash comin' now? Upgraded or fixed the problem yet?
Also, how's life treatin' ya duder? Spend your prize moneys yet? :P

what version of flash are you using? 8? or a lower version? if you stream the song usually theres no problem yet ive had this with some of the submissions ive had in college, i could not get it to work properly so i worked around it, inserting musicand sounds into movie clips, and changing the layout of frames, delaying them/ bringing them forward so once its published into a .swf it works like a charm (yet its a right ball ache)

I may have found a way to solve your problem. Have you tried Action Scripting the sound. 'Kay this is how ya do it. Right click the sound in the library and click "Linkage" then click "Export for ActionScripting" then give it an identifier name. Then on the first frame where you want the Audio to start put this code in.

Sound1 = new Sound(this);
Sound1.attachSound("putthenameoftheid entfierhere");
Sound1.start(0, 99);

Then once you want the sound to stop. Go to the frame you want it to stop and put-

stopAllSounds();

If you don't stop the sound it'll loop endlessly. I've been trying this out lately. Their's never any lag but it is tricky to pull off if you have BG music and soundfx playin' while the line stops. Anyway good luck. That's the method I found.

When are we going to see a new gamer kids??? :( It was so good!