Hello i fitted a new turbo about 2 months ago and the cars been fine ever since but always had an annoying police siren whine since it was fitted but tonight when i was on boost the whine continued right up the rev range so i let off and now the police siren whine is almost completely gone but instead theres a very loud drone noise under load when on boost it sounds horrible the car is boosting but not fully as it should what the hell is wrong with it? it still pulls hard but has that loud drone/whistling noise the entire time im full throttle on boost please help i cant afford another turbo it always got warmed and cooled properly ??

Could be a boost leak. Check all your pipe work.z

sounds like a dodgy turbo or boost leak to me

Update i checked everything and removed turbo intake pipe and had a look the blades are all ok no oil and theres hardly any play and no float in the shaft and i also took a video please watch here https://m.youtube.com/watch?v=BWhQUQ1x1dA

Must be a boost leak then. Cheack all seals and also the intercooler it's self. The plastic shroud can rub through it.

New forge boost hoses ordered hopefully will sort it and let anyone else with same problem sort out there whine/drone