When you have been giving mine a fucking hard spanking and its really nice and warm you can hear the turbo spooling up and a bit of chatter too. Noticing it more with the warmer weather lately. Did you try putting the standard map back on with the dreamscience before you reloaded your tune back onto it? Certainly sounds like you don't have the right map on it, if a boost pipe had split it probably wouldn't boost at all and it would chuck up a fault code.