Causes of overboost?

[AudiiduA]

Hi all, i changed all coils today and car runs much better but the code 16711 knock sensor low signal came back! but this time ran for a few miles before it came back! it was how an s3 should be!
thinking of things that could cause 'pinking', over boosting being one, what things cause over boost issues? i have new N75 and DV
thanks all
Lee

 

[S3KO4]

I am confused as well mine has been ok but lately it boost to 30psi and stays there for a few seconds! if it is not sortted soon I am worried of poping something.