Just fitted a boost gauge to my 97 uk turbo, It's quite a hot day here today and I'm getting around 0.7-0.8 bar boost. I know the ECU reduces boost in high temps, but this still seems a bit low. Leaky dump valve maybe? It does make a bit of the 'blowing over a bottle' noise between 2000-3200 rpm. I'm running on Optimax BTW.

Sounds OK to me. I'm getting 12 PSI (just over 0.8bar) from my UK96. It still feels fast...

Unless we both have the same problem?

IIRC PPP let the boost to just over 1 bar (15-16 PSI)