Whistle sounds coming from tube tv.

My 27" GE tube in the bedroom makes a nasty whistle sound when on, anyone have any ideas?

Assuming the sound is coming from inside the set and not from the speakers, you are likely hearing a subharmonic of the horizontal flyback frequency.

As CRT TV's get older, the laminations in the coils get dryer and looser. allowing the coils to vibrate. This acts as an acoustic amplifier for subharmonics of the frequency the circuit that the coil is in operates at.

Aside from re-gooping the wires around the coil, wrapping them in some buffer material or replacing the offending coil, there's not much you can do.

I turned the volume down, its the speakers...

Sounds like something in the audio chain is breaking into oscillation.

Is it both speakers, or just one?

Does it do it on all audio inputs (tuner, external audio input, etc.)?