Whistle sound from transmission

[DeadMaker]

Ok here is the problem.
When the car is on idle there is a noise coming from transmission.Sounding like whistle or something like air leak..
When i press the clutch pedal the sound is gone,even before i reach the floor.When i release the pedal the sound is on.
Under the acceleration,in all gears,the sound is still there and changing depending the rpm.
So could it be the through out bearing or the input shaft?Or something else?

[kulluminati777]

my clutch slave was making a whistling noise try to hold it while the car is running to see if thats it. I dont know if i need a new one or grease the spot it touches the tranny but i bet thats your noise

[DeadMaker]

I will check it but something tells me it's more complicated.
It's very similar like this..
http://www.youtube.com/watch?v=sjxyuootn6M