Can anyone in derbyshire help with a boost leak

[DIZZYCUPRA]

I have a 2003 210bhp cupra r thats been mapped a while back b4t the last couple of days when driving steady then coming on boost i can hear a funny noise like a jet im getting the normal whistle then this jet like sound comes in the fades out about 5k?

if i launch it through the gears i dont get the noise it only happens when driving steady then start to accelerate, i have spent 3 hours today checking hoses and im pulling my hair out now, im just looking for a bit of help or if someone can give me a hand or even test it for me as i dont know what else to do im in the derbyshire area but dont mind travelling if someone can find itr for me

 

[Feel]

Check the N75 hose where it comes of the charge pipe on the inside - check it carefully, give it a good squidge. Check the DV hose there too. While you've got the engine cover off look for a "Y" pipe at the front right and check that.

Check the fan hasn't rubbed through the MAP pipe.

Split hoses are a beatch to find, try taking it to JBS.

 

[DIZZYCUPRA]

spoke to a few people about checking it for me but they have all said they can only do what i have already done dont want to be paying 50 quid a hour to check something i already have, i have seen people post about using a tennis ball and pumping air in the system this isnt something im sure on so could do with finding someone near me that can maybe do it for me?