Updated to 4.3.6, ANC noticeably decreased

Audible Advocate

Updated to 4.3.6, ANC noticeably decreased

Hi guys,

I bought a pair of Bose QuietComfort 35 Series II end of Dec 2018, they worked amazing for 3 or so months, then all of a sudden everything just stopped working, blutooth, buttons, everything, the headphones were just done for, though my usage never changed, just gently switching them on and off - never leaving my room etc, only used for a few hours at a time at best every few days, barely had them for 90 days.

Then I updated the firmware thinking it might help and the noise cancelling noticably decreased and made everything worse. I reached out to Bose via email but unfortunately there was no reply after 1-2 weeks, so I exhcanged the pair for a new one at the store originally purchased.


The new headphones were perfect again. Which didn't last.

I've had them for less than a week and today after fully charging them I turned them on and noticed a bit of a hissing sound, enough to get annoyed by it, so I quickly updated the firmware to 4.3.6 thinking this might possibly help my fresh pair (I didn't learn) - now even though the hissing is mostly gone yet again the ANC has decreased dramatically - there's basically no difference from low or high, there's no noticable change when switching through the levels of ANC, it just feels like the noise cancelling is switched off - even on high, cars driving past are obvious now, dogs barking, doors closing in the house - all things that used to be completely blocked out are now too obvious. Slightly blocked, but enough to distract and catch my attention unlike before.


I'm very frustrated and thinking of switching to Sony as I just may not have a choice even though I'd much prefer to keep my Bose, I already have no choice but to return this pair again as they definitely aren't working the way they once did after updating. 

I was breifly reading online and it seems like a lot of people are also having this decreased noise cancellation after updating the firmware, is this a recognised bug or issue that might be addressed? Have I perhaps missed something in regards to updates or info regarding this issue? I thought I might just post here in case someone might be able to share some thoughts on the matter as I've unfortunately had a bit of trouble contacting Bose directly~


Thank you for any help! Greatly apprecaited! 

Community Manager

Re: Updated to 4.3.6, ANC noticeably decreased

Hi NeB,


Welcome to the Bose Community Forums. I'm sorry to hear of the issues that you have so far experienced with your QuietComfort 35 II headphones and appreciate how frustrating your experience so far has been. This is unusual performance for the headphones, and I'd love to suggest some troubleshooting suggestions to try and resolve any issues that you're currently experiencing. 


To maximize the efficiency of ANC, ensure that the earcups are seated tightly around the head. Glasses, earrings, and hats may cause the headphone cushion to not form a tight seal around the ear. Remove any of these items and retest the noise canceling feature. I also recommend ensuring that the cushions are securely seated to the headphones. If the ear cushion is not affixed to the ear cup properly the noise reduction or sound quality may be affected. You can find a guide on how to fully install the cushions for the QuietComfort 35 II headphones HERE.


I also recommend performing a reset on your headphones. This can be done by:

  1. Turn off the headset and wait 30 seconds
  2. Plug the headset into a wall outlet using a USB charger, then wait 5 seconds
  3. Unplug the USB cord from the headset and wait 1 minute
  4. Turn on the headset


Should the issue persist, I encourage you to reach out to technical support in your region via out Global website HERE. Select your location, then use the "Contact Us" feature at the bottom of the page and an agent will be happy to assist in resolving this with you.



Andy B - Community Support

Wistful Whiz

Re: Updated to 4.3.6, ANC noticeably decreased

@Andy_B  I am honestly a bit confused or perhaps you are constrained on what you say.  Your response and often the response of the other moderators here suggest that the issue customers here bring up about the hiss and the ANC is not an issue that was introduced by the firmware upgrade to 4.3.6.  You response here, for example suggests that it is rather a problem with initialization or perhaps the ear cushions, lossing fitting - any number of things that you/Bose feel is associated with the customer.  In other words, you suggest that what has happened to this customer TWICE and the many others over the last few months since the firmware release is not anything that Bose is responsible for introducing but rather must be user/customers created.   I have a QC35ii  (AE) and I also noticed and posted here myself soon after the firmware release that I also heard the hiss and change in the what I heard with ANC on HIGH.

Now the group here is obviously not statistically significant and those that come here are obviously those that have issues or problems so the group opinion is obviously 'skewed'.  But what concerns me is that you say 'this is unusual performance' and 'resolve any issues that you're currently experiencing'.


1. This is NOT unusual performance - it is EXPECTED performance once the customer upgrades to 4.3.6.  Those that check in here (and I personally agree based on my own QC35ii) feel that the firmware caused some changes in what is heard.

2. Customers can't resolve the issues since the 'issues' is in the firmware AND you do not allow the customer to regress back to the previous version of the firmware that they just upgraded.  They're only option if they have it is to exchange the QC35ii for another and hope it has the older firmware

3. Bose continues to claim that the upgrade to 4.3.6 had no impact on ANC.

4. If Bose continues to feel the performance is 'unusual' and that it's a customer issue, then Bose does NOT take ownership and they will be no modifications in future firmware to address the 'issue'.

So are the moderators or Bose in general willing to take 'ownership' and observe that the firmware upgraded to 4.3.6 has factored into the observations that ANC has been impacted?


Audible Advocate

Re: Updated to 4.3.6, ANC noticeably decreased

Hi Andy_B,


I appreciate your reply however I'm disappointed in the cut 'n paste nature of it, I have read almost that exact reply so many times now whilst I was searching for others who have also experienced my issue, so I've already followed your mentioned steps, and like many others reported - nothing helped. 

I also reached out 2 times now via email to Bose's support - but sadly I’ve received no response in weeks now, which is why I ended up posting here, as there's nothing worse than not being able to tell if the customer support is a human or some automated robotic response (genuinely not trying to be rude, but those in business must know by now that customers absolutely despise robotic cut and paste replies, it might be easier for mods and staff etc but it's almost never actually constructive or helpful and just prolongs the customer's concern. For me not being able to talk to a human properly about a unique situation is usually more frustrating than the actual problem).


Unfortunately you sort of skipped over my actual issue. I'm certainly aware of enough to have tried everything, like checking the ear-cups and similar,  did the reset and other tips n’ tricks suggested by other users in other discussions, reinstalled apps etc, I did everything I could think of just like what I did with my first pair - the issue certainly doesn't lie with the structure of the product - even if I was able to squash the ear-cups right onto my head by force it's not going to make the ANC better or worse, I can still hear sounds around me that the headphones were previously able to block out minutes earlier before the update, and my low-high options are all the same, there's no distinguishable difference anymore between options in ANC, it’s all just noticeably low/average, enough to cause constant distractions from the noises once blocked.

I also don't wear earrings or glasses, the issue is defintely the product, and even so I've tried everything, I look after all my tech products extremely well - I rely on my headphones greatly, I rarely ever "complain" on forums and this is actually the first time I've ever had to replace a faulty item in my life and/or dig out the warranty and all sorts. I wouldn't waste my time and others just to come here to complain, I was genuinely looking for help or advice from those more experienced in tech, thinking maybe I had overlooked something. 


After further research last night, and reading posts from others, even youtube comments of people reporting the issue after updating the firmware, I can only assume we won't be offered any help or a chance to revert to previous firmware, as it seems like Bose are side-stepping the actual issue and won't be addressing it despite clear feedback, we definitely shouldn't have to beg to be listened to. It's a new update, perhaps there's a bug, kinks are more likely than not - wouldn't that make honest customer feedback more valuable?

If it is a bug or similar, I'd be more than happy to keep my product and wait until it's addressed rather replace my product/brand - I just want to know that Bose are aware of the issue so it actually can be looked into for all those who want to keep their headphones, and for all those just buying their first pair. 

There's nothing more disappointing than a company having hundreds, potentially thousands, of people reporting a clear issue with their new update for it to just be completely ignored - again I’m trying not to be rude, genuinely. It's not even the headphones themselves, it's the firmware.  

I know my issue is not speculation as it was basic cause and effect, it's too obvious that it's the firmware as it happened to me on 2 occasions on two products, as soon as I updated my firmware & turned the product on the issues were extremely apparent and the ANC was definitely reduced to the point it made me anxious just awaiting the next loud sound to alarm me, I was focused the whole time just anticipacting the next loud sound to make it through, I wouldn't come all this way to take time from my busy day, and others, to post about it if I was exaggerating, I was genuinely looking for a solution, wondering if perhaps someone had fixed their similar issues.
It's a shame Bose seem to be assuming it must be something else, like faulty ear-cups on a brand new product, or something the customer has done. I'm honestly trying not to be rude but it's kinda like reversing into a bin on the street and wondering what could have caused the bin to fall over - it was very likely the car that hit it, I'm extremely confident my action of updating the firmware caused my current issues, it was instant correlation, (I fully regret pressing that update button again but I just thought my first pair were faulty).

I honestly don't want to switch brands, I love my Bose headphones (when they work) they're an actual godsend - I've never loved a purchased product more, they were perfect, they did exactly what they were designed for, not one complaint previously at all. I unfortunately feel like I'll have no choice but to return the pair just replaced and look at the Sony ones. Upon returning them I will have to show them this wide-spread issue just so they don't just assume I'm one of those picky customers who's exaggerating or lying, as I couldn't be far from it.
Even so there's nothing worse than experiencing such an interrupting issue, like noise cancelling headphones that aren't cancelling noise, to kinda just have the company ignore it or suggest it must be a different issue (why would we waste time lying?) - fair enough if it happened over time, but not when the product is fine then to update the firmware and then instantly the product is not fine, it can’t exactly be denied, we're all rational and intelligent humans here, the issue is not our earrings, none of us want to be wasting our time running around wondering if someone might believe our honest words. (Sorry if that sounded rude). 
It's like any update for any tech - there's likely going to be some kinks, and maybe not everyone experiences it, but it's silly to just pretend the ones that do are exaggerating or wrong.


Thank you anyway for your time Andy_B, but I’m sadly wasting so much time trying to contact Bose that I think I’ll unfortunately just have to look at another brand, even though I’d really rather not.

Audible Advocate

Re: Updated to 4.3.6, ANC noticeably decreased

Hi joelirwin,


Thank you so much for your input, I really appreciate the time you took add to the discussion, I rambled a bit above haha oops, I'm sure people will think I'm going over-board but I read so, so many posts like night regarding this issue to the point I was just getting angry that it was still being ignored and not even moderately addressed publically, so I maybe let loose a little above, which unlike me, I'm a very understanding person and kinda just wished I could speak to Bose properly about it but I'm sadly convinced that may not be possible now that I know many others share my current frustrations. 

I will unfortunately just have to return my headphones again as I sadly don't think I can wait much longer without them as I use them for work and all sorts, It's very unfortunate as I truly love the headphones when they do work, It's sad to essentially toss aware such a perfect product just due to something like an intangible firmware update, I just wish there was a way to actually speak to Bose and be heard, I've tired so many times that I won't be trying again as I sadly just don't have the time.

I hope they might address the issue in the future for others, it seems like a lot of people are being affected. Thanks again for your input and time to write and help the cause! 
I always feel terrible when getting frustrated on product forums, almost guilty for maybe coming across rude, but yeah I read a lot of stuff last night and unfortunately way too many customers have been ignored and it jut doesn't seem right.

I usually avoid forums as I know how easy it can be to accidentally annoy people or cause more stress beyond the issue haha, which is not what I want to do when reporting a genuine issue, but at least it's somewhat comforting to realise many people are experiencing what I am, hopefully I didn't come across rude in my above post! 

Thanks again for your input, hopefully the issue will be acknowledged sooner rather than later~

Wistful Whiz

Re: Updated to 4.3.6, ANC noticeably decreased

1. I have posted this in other threads but it also is so relevant here as well.  In Bose's discussion/argument for supporting only the latest version and not providing the ability to reinstall a previous version, they claim among other things, that the older version may have bugs and it makes it harder for Bose to support.  What they fail to point out is that if you upgrade from version A to B, you were already on A - all that is being asked is to go back to where you started.  While it may be true that the trend for vendors is to support a single version, there is still the concept that Microsoft, for example supports called, a "Restore Point" or "System Restore" .  Effectively it functions as an installation 'undo'.  No one is asking Bose to do more than they already do.  We are not asking them to provide an installation of a previous firmware version to just anyone.  What we are asking is to save for a short period of time (say a day or something like that) the current fimware during a firmware update.  That way if the customer wants to go back to what they had, i.e., a 'firmware restore", they can do so.  Doing so does not require any different support stance from Bose.  All that is happening is we go back from B to A and "A" is where we started. Bose were already supporting us with "A".

2. You said: "I just wish there was a way to actually speak to Bose and be heard" - Google and get the main number for Bose HQ in Framingham, Mass.  Not the support number.  Then ask to be connected to the Customer Service Manager.  For privacy I will not include the phone number or his name here but will say the last name starts with "R".  He is a caring person.  He listened to me twice.

Audible Advocate

Re: Updated to 4.3.6, ANC noticeably decreased

Agreed. In my case, I had a brand new Bose QC 35 II which shipped with the firmware 4.1.3. On the way back home from buying the headphone, I tried it out and was amazed at the noise cancelling, it completely silenced the car I was in. I felt very noticable pressure in my ears from the noise cancelling but was willing to live with that in place of great noise cancelling. On that same time however, I noticed on my phone the 4.3.6 firmware update in which I updated to. I was using the headphones while the update was doing its thing.


After the update there is now no pressure from noise cancelling however I feel that the noise cancelling is inferrior as I can now hear the car and as you said @NeB, there is no diffrence between high and low anc. I did notice a diffrence in one instance on a windy day where on high I would hear interference  from the wind but on low this was eliminated.


Now I shrugged it off as I only used the original firmware for about an hour before the new firmware 4.3.6 and thought maybe its just my mind and other posts are about older firmware versions. But your post, increasingly raised my suspicion on this issue. Almost makes me think that the new update was meant to reduce the pressure on the ears due to ANC as many complained on the internet which results at a cost of ANC performance but I maybe wrong. My headphones were manufactured in 19 November 2018.


Now when I get time, I will visit stores which have the Bose QC35 II in display and comparing it to mine to see if my unit does have worse ANC and will also give me proof.


Re: Updated to 4.3.6, ANC noticeably decreased

Hello NeB, 


Thank you for your reply to my colleague, Andy B. 


I have looked into this as best I can currently, and can see version the 4.3.6 update brought in the following changes: 


Released 6 Mar 2019

Version: 4.3.6


  • Added groundwork for AR functionality
  • General bug fixes and stability improvements

Please excuse me for my lack of detailed information, this is the full extent of the details we are provided on the customer service side regarding firmware updates.


Andy provided you with typical troubleshooting that we recommend when a noise cancelling issue occurs with our line of noise cancelling headphones, while this may not have assisted in this instance, there is always the chance that something he suggested may have helped.


Now, it looks like a number of people have suggested having the same ANC issues as a result of this update, and I can completely appreciate that having a feature that worked initially unexpectedly change in a firmware update is not the best experience for anyone. Please trust me when I say I fully intend to investigate this within our internal escalation team so I can provide you and the rest of the community some answers, and more importantly a resolution.


Please bear with me, I'll be back in touch as soon as I get responses from the team. 


In the meantime, have a fantastic rest of your weekend.


Kind regards,


Jeff G

Audible Advocate

Re: Updated to 4.3.6, ANC noticeably decreased

@joelirwin wrote:

1. This is NOT unusual performance - it is EXPECTED performance once the customer upgrades to 4.3.6.  Those that check in here (and I personally agree based on my own QC35ii) feel that the firmware caused some changes in what is heard.

2. Customers can't resolve the issues since the 'issues' is in the firmware AND you do not allow the customer to regress back to the previous version of the firmware that they just upgraded.  They're only option if they have it is to exchange the QC35ii for another and hope it has the older firmware

3. Bose continues to claim that the upgrade to 4.3.6 had no impact on ANC.

4. If Bose continues to feel the performance is 'unusual' and that it's a customer issue, then Bose does NOT take ownership and they will be no modifications in future firmware to address the 'issue'.


I agree whole-heartedly with all @joelirwin statement above.  Several people voiced their concern about the decreasing ANC, but yet Bose standard copy-paste answer is reset your headset and if problem persist, contact your local Bose.  When I called them, in essence I was told that the issue just in my head/imagination.


Bose, you don't have to support all Firmware version, but at the very least give the customer the ability to "roll-back" to the previous FW version.  With that said, @Jeff_G, we are waiting for a solution as you mentioned on your post. 


Thank you, 


Your loyal Bose customer



Audible Advocate

Re: Updated to 4.3.6, ANC noticeably decreased

Hi @Jeff_G, any updates on this issue from your internal escalation team?  

Thank you,