Why? after home hang and resume, APP play more smooth on ipad/iphone

On ipad/iph.

Start app,

load and play swf,

Sounds bad, choppy!

Start app, then use Home button, hang and resume app,

load and play the swf

Sounds well,smooth!

Why?

I guess that hanging load all air native machine to Ram,

So resume play smooth

who know how to use the trick?