sounds like a air leak when i put it in drive.
 

i jus got a 99 integ se automatic not to long ago.. i noticed i could hear a air leakage only when i put the car in D(drive)... in Park it would go away.. what is it? it sounds like some compressed air is leaking or something.. its not loud, its very light you can barely hear it

does it do the same thing in reverse?

Probably a vacuum hose that fell off or is cracked/broken somewhere in the engine bay.

thing is whenever i drive an automatic. when you pull it into the engine has a bit of torque and it pushes against the power of the foot brakes. so i'm assuming it might be that.

if it were a vacuum hose you'd also notice some fluctuating idling.