Humming noise at various cruise speeds.

[shelbymann]

So I have a noise loud enough to vibrate my interior panels.2025 EQ. 6500 miles but I have noticed it sporadically and it got worse last weekend. So every time my foot off the gas the sound is close to driving over rumble strips but of course not a rumble strip vibration. Almost like a loud exhaust. 2 days ago it was so bad it would do it at 65,55,45,35 and even at 10 miles an hour. Never under acceleration. So I was going to take it to the dealer and I had a lot of weight in it as in 100 lbs of dumbells(car show cover weights) a bunch of chairs and a car cover. I took all those things out to were no weight behind the front row of seats. yesterday and today I have been in various driving conditions from 10-60 miles an hour and NO NOISE. The diff is the extra weight. Weird. I thought it was a muffler back flow thing but like I said it happens when their is weight behind the front row if seats.

 

[Hey Vern!]

I wonder if the noise cancelling was picking up noise from those items in the car and tried too hard to cancel it.

 

[Rad10eng]

Does this sound familiar

 

[Rad10eng]

Does this sound familiar

My son and I actually traced the noise to the rear speakers. Using my spectrum analyzer, the fundamental frequency is around 62 Hz, it is accompanied by a train of odd and even harmonics. This appears to be an issue with the audio DSP. The dealer is supposed to have a fix. They just set up an appointment for me tomorrow. The fix is part software update, part mechanical. The little mic screens next to the grab handles kept falling out in our car, they finally got lost. It appears that GM has newly designed mic screens that come with a template. They need to be adjusted to null out the resonance. Yeah, I am an audio geek! Please take note that the noise is worse between 1800- 2000 RPM

 

[shelbymann]

thanks. I'll let them know. I got my courtesy oil change today and left the car at the dealership due to a leaking trans. seems the Mexicans building it have problems torquing the trans bolts.

 

[shelbymann]

I wonder if the noise cancelling was picking up noise from those items in the car and tried too hard to cancel it.

thanks it could be that also as there is a service bulletin out on that.

 

[PeteComp]

I had the exact same problem which took 3 trips to the dealer to find out the problem and fix it. Yes, it turned out to be the ANC and a loose mic under the headliner. However, that only helped but didn't solve the problem. They then had to do a forced radio software update which finally fixed the problem. While they had it, I asked them to install the Universal Remote which was missing in the 2025. They did it! I haven't tried it yet but I'm assuming it will work.

 

[Rad10eng]

thanks it could be that also as there is a service bulletin out on that.

I will get the number tomorrow and post it. I will know by the time I get home if it worked.

 

[Rad10eng]

I had the exact same problem which took 3 trips to the dealer to find out the problem and fix it. Yes, it turned out to be the ANC and a loose mic under the headliner. However, that only helped but didn't solve the problem. They then had to do a forced radio software update which finally fixed the problem. While they had it, I asked them to install the Universal Remote which was missing in the 2025. They did it! I haven't tried it yet but I'm assuming it will work.

Are you referring to the universal remote garage door controller?

 

[PeteComp]

Are you referring to the universal remote garage door controller?

Yes. Mine did not have it until they did the software upgrade.

 

[shelbymann]

My son and I actually traced the noise to the rear speakers. Using my spectrum analyzer, the fundamental frequency is around 62 Hz, it is accompanied by a train of odd and even harmonics. This appears to be an issue with the audio DSP. The dealer is supposed to have a fix. They just set up an appointment for me tomorrow. The fix is part software update, part mechanical. The little mic screens next to the grab handles kept falling out in our car, they finally got lost. It appears that GM has newly designed mic screens that come with a template. They need to be adjusted to null out the resonance. Yeah, I am an audio geek! Please take note that the noise is worse between 1800- 2000 RPM

My car does it at 1900 RPMs like your video implies. I don't think it is speakers doing it as my vibration is only at 1900 RPMs so tied to engine "performance" not audio sounds. Does this make sense? Mine gets really loud now. It is various auto trans gears as it will do it when going under 20. I see it pronouncedly going up a hill and my speed (usually 62) drops the RMPs to 1900 and it vibrates like hell from the humming noise.

 

[PeteComp]

My car does it at 1900 RPMs like your video implies. I don't think it is speakers doing it as my vibration is only at 1900 RPMs so tied to engine "performance" not audio sounds. Does this make sense? Mine gets really loud now. It is various auto trans gears as it will do it when going under 20. I see it pronouncedly going up a hill and my speed (usually 62) drops the RMPs to 1900 and it vibrates like hell from the humming noise.

That's EXACTLY what mine did. EVERY gear under a load, always at between 1800 and 2000 RPM. I would bet anything that it is the same thing. I NEVER would have thought it was audio sounds. When I put my hand on the door panels they would vibrate like my wheels were falling off. I would bring it in and have it checked. However, if you don't mention the ANC issue, they won't look for it. As I said in my previous post, I had (according to the dealer) both a loose mic AND had to reprogram the software. Good luck.

 

[shelbymann]

That's EXACTLY what mine did. EVERY gear under a load, always at between 1800 and 2000 RPM. I would bet anything that it is the same thing. I NEVER would have thought it was audio sounds. When I put my hand on the door panels they would vibrate like my wheels were falling off. I would bring it in and have it checked. However, if you don't mention the ANC issue, they won't look for it. As I said in my previous post, I had (according to the dealer) both a loose mic AND had to reprogram the software. Good luck.

Thanks. I screen shot this for my service advisor. It is definitely a lot worse now than when new(getting looser?).

 

[PeteComp]

Thanks. I screen shot this for my service advisor. It is definitely a lot worse now than when new(getting looser?).

Be sure to mention TSB 24-NA-182. That is their Technical Service Bulletin which states the problem.

 

[shelbymann]

So far…

 

[Hey Vern!]

So far…

sounds like you are on the right track.