Did anyone notice that when pressing the gas pedal or the brake during 25 - 70 km?
You will hear the high-frequency sound like vee~vee~ (not the hybrid UFO sound).
That noise is pretty annoying to me and gives me a headache sometimes.

 

I have not noticed anything headache inducing! The opposite, when enjoying the drive and listening to music!

 

Like really high frequency? I think I know what you are talking about. And it's not the hybrid sound.

I've asked the dealer one time, they said they didn't hear it.

For my situation, it's not always making that sound. But so far, I couldn't find the pattern yet.

 

I noticed something like this the other day. I would hear it when the heat was turned on and fan blowing. When I turned off the heat the noise seemed to stop.

 

Yes lately it has been really annoying. I noticed it only just started in the winter. The sound is like a high pitched whistle like a dog whistle or something. Definitely not the ufo droning sound that we are all used to.

 

If it’s not too much trouble, can one of you record the sound you’re hearing? I think I may be experiencing the same thing. There’s a faint, high pitched noise I hear that I thought might be coming out of the speakers, but it’s hard to tell. I just want to make sure it’s a natural noise or if it’s something i need to bring to the attention of the dealership. I also own a 350h.

 

That’s the exact sound I’m hearing as well. As mentioned I was able to recreate the noise by turning on the heat, and when turning it off the noise would stop. Will try and get a recording.

 

I know for sure it's not the radio. I've tried with radio ON and OFF, the noise is always there.

I have not tried heater yet, will try it next time driving the car.

 

I've reported that sound back in the summer when I 1st got the NX, but the dealer could not hear it. I've changed out the flat-tires for normal winter tires and have not experiencing that noise - sound anymore.
But FYI, I only hear the noise with the windows down and drive slow like you've mentioned.

 

I’ve tried with the heater off and on. Doesn’t go away. Would it possibly have something to do with the current weather conditions we are having? I noticed it only started happening in the winter.

 

I also confirmed it's not the heater. And for the past few trips, the noise is gone. Not sure what triggered it making/not making the sound.

 

I have not been able to replicate the noise. Only occurred to me the one time, it was late at night and very cold out, -12C

 

There are two things I think it could be:
1. Electric traction motors - does the sound pitch change if you accelerate and brake?
2. nanoeX filter thing in drivers side air vent, open the climate shortcut and turn it off

 

Could be the heat pump. I get a pronounced whirring at low speed, driving short distance and ambient temperatures around freezing

 

not a whirring sound, more like a high frequency whistle. Like a dog whistle. That’s what I’m getting at low speeds. But once the speed gets down to when hybrid mode turns on the ufo sound starts and the high pitch whistle stops.