2004 A4 not revving
 

So this has happened to me on two occassions, both after slamming on my brakes in an emergency stop.

Basically, I slam on my brakes and my car dies, then when I start it back up and step on the gas nothing happens, car won't rev. It's almost like the tranny locks up. It takes a while for me to get the car to start going again.

My car is chipped with APR stage 1+ software.

Anyone have any idea what could be causing this?