I have tried several mb and mbp, and they all cause a very high pitched noise in my ear, similar to a tinnitus. this noise is not really noticeable right away (like the inverter-caused noise that some 17 inch hi-res sr mbp seem to have). the sound appears after a while of use, and it stays pretty long time. it really bothers me quite a lot. (old macbooks did not have this issue. that's why I think it is the led-display.) I don't know what to do - I just want to use one these macbooks. they are awesome machines besides this strange noise issue. i have tested it by recording through a microphone, and there is a very little audio peak round about 19500 hz - but this may also be the hard disk. does anyone happen to have experienced similar problems?