Hi,
I noticed the air intake pipe is connected slightly un-evenly and there is a thin groove around the pipe which looks like there should be some metal clip. There is a jubilee clip on it but thats like 4cm further up.

About 3 months ago, my turbo blew. Prior to that my car was whistling when I accelerate. So a so called diesel specialist changed my turbo for a brand new one and now it is starting to whistle again, but not as loud as before.

Ofcourse I have to take into consideration other pipes/hoses... like the rubber hoses on the intercooler are oily/greasy so I will change them asap.