Engine bay squeal

[Magnesium]

For the past few weeks I've been noticing a squeal when the car is up to temperature, which lasts for a few seconds, haven't been able to reproduce it myself but tends to be after approx 30 miles of motorway driving. Switching the AC off doesn't stop it neither does tapping the brakes, the note and volume are the same regardless of speed. Originally it was only happening above 30mph approx. On one occasion after the squeal I pulled up to traffic lights and the car began misfiring until I pulled away. Today after parking up the noise continued long enough for me to film it, it's definitely coming from the engine bay but couldn't tell where. Anyone else had this? Bog standard DSG model if that helps.. VCDS didn't find a thing

Video here:

Any help appreciated! 

[amanda]

Squeal is normally a belt

[pudding]

Remove the accessory belt and run the engine again. If the noise is still there, it's likely the turbo I'm afraid to say.

To confirm that, drop the down pipe and check the shaft for in-out play.