'02 3.0 Whistling Noise Acceleration Need Advice

[gollum]

Upon intial normal acceleration and the when maintaining speed, but not during hard acceleration, I get a whistling noise. It sounds like a bird chirping without the chirp, just one long continuous whislte.

I took it to the dealer and they explained to me it was normal, that it had to do with the DISA valve. I have searched for this problem already on these forums, but with no luck on finding any info. I have also googled it, to no avail.

Question: Is this sound normal? I did find one article describing a problem close to this, it also said that all bimmers do it to some degree. However, I have driven in several X's of varying types and have never heard it. I suppose I could be more sensitive to this high piched whistle than others, but all the service coordinators and techs heard it, so I think not.

My dealer is ordering a new DISA valve to see if it helps.

Any opinions\links\advice would be greatly appreciated......