Faint, high-pitched whistling sound

[MWD]

Just heard this sound for the first time. New My17, stock, about 800kms so far.

Will check more tomorrow, but so far I have only heard it clearly in 6th gear at 100kph (~62mph). I might have heard it at different speeds/in different gears but I can't be sure because it was late, I was tired. It's more noticeable when I let my foot off the accelerator after feathering it a bit (highway drive home) since the high pitch will lower and stand out against the drone (?) of the exhaust.

Touching the accelerator at all, like even just resting a slight pressure on the pedal will cut the noise completely, then feathering will restart it etc.

Tea kettle noise is a good way to describe it, my initial thought was like a Roadrunner cartoon sound effect where Wile E Coyote starts falling off a cliff, but the sound byte gets cut 1/4-1/2 way through so the pitch goes higher down to high, no low end etc (if that makes sense).

I can't check that video to confirm the noise.

Some people say it's a normal differential sound (in the other thread Subie iirc got his differential replaced but still had the same sound). Some people haven't heard the sound with their twin (those comments worry me). Others say vacuum or exhaust leak. One guy said every '4-banger' he's owned has made some kind of whining noise in top gear at medium-low speed, usually when the gas pedal is being pressed slightly.

Once the car is broken in I'll be taking the car on a long road trip, and man will that sound get irritating after a couple of days. I will talk to the service department at my dealership and see if they know what the issue is.

No one seems to have found a definitive fix, perhaps something is not sealing properly.

Things I haven't tested yet:

- If it occurs when engine is cold.
- If it occurs at idle.
- If it occurs at at 56.327kph (35mph)
- If it occurs with sound hole plugged.
- If it occurs in any other gear except 6th.
- Checking for leaks.

[Sgaldi]

Just noticed my car making this whistle noise :/ all these weird noises are starting to make me think I should have bought somthing els...for 30k you expect a certain level of quality

[kmbkk]

Reviving this thread as I’m getting a whining noise in 6th gear now as well. The noise starts becoming audible at 70 mph but is more noticeable at 75 and much louder by 80. It goes away immediately if I let off the throttle, and comes back when I give it a little gas again. I thought at first it was alternator whine coming through my speaker, so I turned off the radio and it was still present. I turned off the AC to make sure it wasn’t the compressor, bust still present.

I first noticed it on a long drive last month, then again coming home from work today. I’ll keep trying to figure out what the problem is but appreciate any suggestions.

[Ultramaroon]

It's differential. Shift down to fifth while it's happening. Modulate the throttle more gently than in sixth and I bet you'll still hear it. Normal.