faint irregular beeping while moving forward

I bought a 2009 Prius, called a demo by the dealer as his wife used it and put just over 5000 miles on it. I've had it for only 19 days and drive it every day.

About a week ago, I noticed a faint, irregular beeping or whistling that seems to come from the navigation console. It seems to happen when I'm moving forward, particularly when the gasoline engine is NOT running. I hear it when coasting or on electric motor and occasionally when I brake-right before the car stops. I do not hear it when braking slightly or momentarily and never when the car is at a complete stop.

I think it's more of a whistle, but my husband and son say it's more of a beep. My son thinks it's a computer sound related to changing conditions of the fuel system.

My husband walked along the outside while I drove slowly. I could hear it inside, but he could not hear it outside. It is not related to the audio or climate systems and is heard with the windows closed. It is not the screws under the door mirrors. I checked them and all the plastic covers are intact.

There are no warning lights and the noise is not always there, but I will hear it at some point during any trip in the car. (My commute is about 25-30 minutes at 35 - 40 mph.)

I spoke to the service department about it by phone and they had not heard of this, though he suggested some sort of 'feedback from the navigation system.' He wants to keep it a whole day to check it out, difficult for me, as the dealer is not located nearby.

Any ideas? Should I even bother about this?

Thanks.

Kris

 

If interested, please see replies to this same thread in the Prius II Main Forum. Thanks.