20Sierra14

It's been six months and the cotton balls still are working for me. After a few weeks of the tape being in the heat, it'll start to fall and expose the openings for the mics and I'll start to feel a little pressure again. The cure is to pull the 4 cotton balls I have stuff in and around the mic openings and install new tape and cotton balls. Zero headaches and pressure. Again, our truck has no buffeting issues, though. Just ear pressure that would bring tears to your eyes!

I believe there are two types of "noise reduction" systems that GM is using... One is "ANC" that is actively listening to the noise in the cabin (with the exposed mics) and the other is one that is simply tied to the RPM level of the motor to reduce engine noise. Both of which pump a frequency into the cabin to reduce the noise, thus giving some folks a headache. I looked over the ATS's roof lining as well -- No exposed mics, meaning no ANC. For whatever reason, the ATS just felt right inside. Edit: Wrench, you said it well in another post: "What we don't know is if the "non-ANC" still have some active noise cancelling based simply on engine rpm. Bose does have technology for that, too, that simply outputs a known sound to cancel known sounds that come from the engine at certain rpms. Thus, not a full feedback noise cancelling system but a simple "open-loop" type system. GM does do this on the Terrain, so it's possible its used on all the full size, and the top trim levels get the full feedback system added on."

Here's a little fun twist - This past weekend I went to Vegas and had two GM rental cars - A 2015 Malibu and a 2015 Cadillac ATS... Would you be surprised if I said the Malibu generated the SAME head/ear pressure as our 2 Yukons??? The extent of the pressure wasn't as bad, but it certainly was present! On the other hand, the ATS was perfect. No pressure issues with that car at all. The Malibu isn't optioned with a "ANC" system (just as the regular Yukons) but for whatever reason, it still generated pressure... This is simply another example that the "sound reduction" system these vehicles are using is precisely what is creating the ear pressure - no doubt about it. Now...why did the ATS not have the issue - I have no idea.

1) This topic is crazy, but going back a few months, I was one of the first to try the AMP fuse pull.. It helped my situation for only a couple days, then the pressure came back. Muting the mics w/ the cotton balls has been the ONLY solution I've found to work -- and it's been working for a few months now.. No more headaches. 2) No, I have not tried it without the truck running.. I was trying to focus everything possible to get the ANC to "hear" the "boom" I was creating, instead of the noise the truck is making going 35-40mph. I can sure try it though. BUT, hearing your situation, this focuses the ear pressure is being produced by the ANC even more! How can a truck that isn't even rolling create pressure? Nothing is moving?!? Ahhhhh-- the ANC trying to keep the cabin nice and silent!

Pic came out cool, so made it my sig too!

Windows up, AC won't affect anything, radio off and yes, around 35-40mph... Our 1st SLT was on 20in wheels and had buffeting and ear pressure. This truck was brand new w/ 3 miles on it when we drove it 2hrs back home... We did not notice any issues on the way home, but everything started a couple days later w/ around 300miles on it.. See if your dealer is willing to do a "few-days" test drive before you sign anything. Best of luck!

I totally believe that the buffeting and the ANC work together to create the "total sensation." Our Denali has ear pressure, but has zero buffeting. This leads me to believe that if you have the buffeting, even the cotton balls won't fix the pressure. To test my idea, I started the truck and banged on the headliner... Yup, ear pressure -- from a standstill and cotton balls! This assures (to me) that the pressure itself is 110% from the ANC... If you have buffeting and ear pressure, there is no way to "trick" the system to rid the pressure. This also helps the other theory, that if you have buffeting, the pressure is enhanced. I really believe the whole situation is a "reverb" effect -- whatever is exciting the noise that the ANC is trying to cancel converts into the booming/buffeting noise everyone is hearing. Again.. just my ideas and input is purely subjective

Reference back to the cotton ball trick I did w/ the mics.. It takes literally 10 mins to do.. Since you aren't experiencing buffeting, the pressure can be fixed by deafening the mics. Edit: I'm going on 8 weeks now w/ no pressure.. I did have to replace the cotton balls w/ fresh ones, but so far, it's worked perfect for me.

Have this same problem in my 2014 Sierra and now our 2015 Denali has started doing it... Told the dealer about the truck months ago, but the "shim" kit was back ordered. I'll hit them up again on the next oil change.

That is certainly not enough material to "mute" the microphones. Ultimately, it does looks better, but if you're still getting dizzy, go aggressive (and ugly) and shove a bunch of cotton around the entire microphone and base - not just the inner ring.

Same here... Fresh cotton balls did the trick

I'm more than happy looking like a "buffoon" with my cotton balls... You know why? It fixed 95% of the pressure I had... Have you used the idea yet, or have you simply used a cloth and tape? "JasonDenali" had his dealer actually use the idea and it seems to be working for him... Are we "idiots" now? It seems your vehicle is having more problems than this topic will cover. Have the dealer distroy your truck and replace whatever they see fit... You keep referencing back to the roof fix, when more people have stated it didn't work.. Try the rearend replacement, and like Zip said, post up if that fixes it.

Finally! Someone stuck to the basics!! Lol!! Keep us posted to your results! Going on a month now with no more headaches for us!!

I was able to get them off with my fingers... No damage done to the grilles.

This is extremely concerning -- for you and me both! Here's my experience -- A couple weeks prior to my "cotton ball" idea, my wife, who is the primary driver of our Yukon, was experiencing extreme dizzy spells at work. She never told me she was getting headaches like our 1st Yukon SLT, but she was getting these random dizzy spells a couple times a week. I didn't think much of it and certainly did not associate it to the Yukon -- but guess what?? Ever since I "silenced" our ANC mics with cotton balls, she hasn't ONCE had a dizzy spell! I remind you, I never hinted it could be the Yukon causing the symptoms -- As bad as it sounds, I observed her symptoms to test my theory... Guess what -- It worked! Ever since I've "silenced" the ANC mics, my wife has yet to have another spell! This is why I'm 110% positive the ANC is the root of our ear pressure/headaches! But FOUR, I really hope this isn't something permanent - and certainly NOT something caused by these trucks! Keep us posted!

Huh? This thread and the other are no where near the same.. This one has taken to the point of FIXING the issue, the other is to compile a list of people who have the issue ONLY -- not to simply start over. That would be dumb. If the other thread would create utter confusion (or you to stop your research), I'll have it deleted.

You are 100% right about needing to re-pack the cotton balls! The cotton I originally used a few weeks ago has now been "squished" down to the point to where they won't be as effective. I'll get you the measurements when I replaced the tape and cotton. Just to be sure, you're needing the depth of just the foam O ring..? Not the whole opening where the mic is exposed? Also, I PM'ed you a pic of the ANC mic grille. If you missed it, here it is for everyone else:

No, the openings are NOT enclosed... My fingers can feel all around the back of the headliner.. In other words, I think the mic is mounted the metal roof and then headliner was just placed on top. The mic doesn't seem to be concealed off in its own space. Edit: I just ran out to check.. the mics are NOT concealed to their own enclosed space.

Sorry for late response.. If you ever need some info, quote me - I'll get an email when you do Depth - I don't have anything to measure that small, but maybe 1/8th of a inch..? Soft Cannot be removed - Glued (most likely) to the plastic behind it About 3/4 of an in wide Some squishy, sound-deadening foam.. Proper name? No clue.

Nothing.. Stock Denail Q7M wheels.

22in Bridgestones here.

Nothing from our's.. Rides perfect, no buffeting, just horrible pressure (w/o the cotton balls) Most certainly have them disable ALL THREE.. If you just have one disable, it would/should make the system "over-compensate", thus making the pressure worse -- as you stated! It just make sense that it's the ANC creating the pressure! To me, I think it's a "reverb" effect from road noise into the ANC system that's creating the buffeting noise. Just speculation, though.

GM has already tried to fix this the roof..? What other part of the roof would be causing the buffeting? Now the "buffeting" sensation could be enhanced due to road noise being generated up from the road into the cabin, then being heard by the ANC.. This could create a reverb sound (aka, what I would call, in my book, buffeting)... Please forget the tape and cloth and be more aggressive w/ the cotton balls and tape.

I'll plan on using them once GM gets their crap together! Who knows when that'll be, though! You seem like a legit guy, I'll just PM you our VIN

No, the grilles are sitting in the cup holder. There's no way to put 2.5 cotton balls in that space and still re-install the grille -- that's where the masking tape comes into play.. It looks absolutely horrible, but my ears appreciate it. ateam_burb is heading the right direction! Give us the option of turning ANC ON AND OFF - problem solved, GM isn't having to buy back trucks!