(T) 1.6 Whining Noise?

hello.any ideas? ive got an 03 1.6 5 door and im very pleased with it so far.
the niggling problem (hopefully) is that whrn i take my foot of the gas , and the car is de-cellerating, it gives a real whining noise. sometimes its louder than others, but it seems to dissappear when the clutch is in, or its in neutral.
im worried it might be gearbox related, ( hopefully just oil change ) but just wanted your highly esteemed opinion first please!

This sounds like the exact same problem I had- twice.

And im affraid its sounding like its leading to a gearbox failure

See my threads here, here andhere and here

doh! was it under warranty or did you have to pay for geaqrboxes???