Possible locations to check for air leak

[cornflakes2]

I was having some air leak under load, most noticeable at low speeds, while turbo was "overspeeding" (working a little harder than it normally does at that load and low speed...this is due to air leaking and not enough air getting to the engine so the turbo working a little harder to try and make up for the lost air).

A shop told me to try and replace the APR intercooler hose charge pipe and outlet pipe so we did that and I can say the acceleration power has come back by around 60% and definitely hear less air/whoosh sounds when I accelerate but it's still not up to par. I can still tell it's lacking power more than it's supposed to do. I suspect there is still some air leaking somewhere else.

Any suggestions?

(TFSI 2.0L gasoline EA113) VW Scirocco.