Un-known Engine whistle

Hi,
My defender 300tdi has suddenly developed a whistle and im unsure of where it is from. I have never noticed the whistle before, but lastnight you could hear the whistle when it was reved and it was fairly loud but sounded nice to be honest. The power increase since the whistle has arrived has definitly increased, it doesnt feel like my landy its that much better. I havent got a clue what as happened as im new to landys, but so far it seems for the better. But i dont want to do any damage.

If you guys wouldnt mind giving me a bit of advice on the possible causes please.
Many thanks Josh

split turbo hose? something in the air intake? Turbo bearings?

my disco 300 did this it was a hose that came loose between the turbo and intercooler and yes i got a wee bost to power that i thought odd , sounded like a scooby with a dump valve if you reved it just rite

turbo hose leak/split

mine does it on my 200tdi. it is turbo related but i have no leaks in pipework and can only be heard when moving. its done it for 8 odd months now with no issues. if it whistles about 2 second after you put your foot down then i'd say turbo. i stripped mine down and was a ok. no help at all really.