Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

Community Manager

Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

March 7th - Moderator note: There is updated information located in this post: QC35 Issue Updates.


Update 2/3:


Hi everyone. 


Thank you all for the very specific and helpful information many of you have provided.  Our team is using this information in our investigations into determining the root cause and developing a solution.  We plan to have additional information to share early next week. 


Thank you for your patience.


Update 1/26:




We’ve been closely following the recent posts here by users sharing concerns about their QC35’s audio quality following our recent 1.2.9 update.  We’re as passionate about sound as you are and understand the frustration expressed in these posts.  A method for reverting the QC35’s firmware was posted here previously and we are glad that it has helped many of you.  Note that this method is not recommended as it is untested and cannot be verified by us to not potentially damage your product. 


As a result of your feedback, we would like to offer an alternative to assist those who wish to revert their firmware as we continue our investigations into the reports provided here in this community.  Our product teams are extremely thankful for the valuable information provided here and encourage users to continue sharing their experiences whether they choose to perform this procedure or not. 


It's also worth noting that although the Bose Connect application does not need to be uninstalled, the new features introduced in this version, such as Music Share, will not be available.  Release notes for this version can be found HERE for more details.


Users who choose to revert should ignore any prompts from within the Bose Connect app to upgrade the QC35’s firmware as this will return them back to the current version.  


Here are the instructions to initiate the firmware downgrade procedure:


1. Go to on a PC or Mac computer

2. Plug your headset into the PC or Mac via USB

3. Click on the QC35 product

4. The update page will load and tell you the software is up to date


Revert 1.png


5. When on this screen type the following 5 keys sequentially: ‘a’ ‘d’ ‘v’ ‘<up arrow>’ ‘<down arrow>’.   The page will display the following:


 revert 2.png


6. Choose 1.0.6 from the drop down menu, then click “apply changes”


 revert 3.png


7. The Firmware will begin to load.  This process may take between 5 and 10 minutes depending on ISP and network conditions.  Do not disconnect the headset until the process is complete.




1/25 - Moderator note:  We wanted to provided an updated note from our Bose Connect team regarding the issues brought to our attention in the previous post.


Hello everyone.


We want to assure this community that we hear you and are actively investigating the reports provided here. Thank you for taking the time to help us better understand your issues and this feedback provides us valuable insight.


We thoroughly test our firmware and software internally and with 3rd parties. Our acoustics are measured in many ways in our labs and with critical listeners at Bose. All this is done before firmware gets distributed to our customers. We take audio quality very seriously and continue our attempts to replicate the concerns reported by some users here.


In order for the community and our product teams to find the information they are looking for, please report only audio quality issues (lack of bass, distortion, etc.) in this post. Users with any other types of issues (connectivity, Bluetooth issues, etc.) are encouraged to create their own post for assistance.


Please continue to use this post to provide us the following information which will help our ongoing investigation:


(Note: Users who provided information on the previous post do not need to provide it again.  These details have already been shared with our engineering teams.)


  • Description of the issue.
  • Manufacturer and model of the mobile device tested with.
  • Software version of the device being used.
  • Bose Connect app version.
  • Product firmware version.
  • Any potential solutions users may have found on their own.
  • Source applications used (Spotify, Pandora, etc.).
  • Are you using any built in or 3rd party sound enhancers or equalizers on your device? Yes or no? Did you notice any change by disabling or enabling them?
  • In your device's Bluetooth settings, is your headset connecting to BOTH the call audio (HSP) and stereo/media (A2DP) profiles? If not, please provide additional details about the behavior.


All information provided here is helpful and welcomed. Note that due to the sheer number of variations between computers, information about iOS and Android devices is most valuable at this time.


As we learn more we’ll keep this post up to date. We recommend subscribing to or bookmarking this post for the latest news as it becomes available.


More to come.


Thank you,

Bose Connect team.

Quiet Contributor

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

Hello Jason,


Just updated my headphones.

1. Tried them for a couple of seconds and I could tell right away the sound was completely off. The bass doesn't sound deep at all and the rest just sounds hollow, flat even. It has lost a form of depth and contrast between noises; like loss of immersion. It is very difficult to explain, but something is completely off. It is no where near as refined, could also describe it as tinny or rough at the top ends. It just feels flat. The same goes for a wired connection.

2. Tesetd with iPhone 5s iOS 10.2.

3. Latest Bose connect app as of today.

4. Firmware version 1.2.9

5. Using Spotify, 320kbps streaming, noticeable drop in sound quality since update.

6. No equalisers.

7. Bluetooth settings on iPhone cannot be messed with.


Please release notes with each firmware update! I would love to downgrade so badly! Is that an option?





Silent Starter

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

I totally agree with remyc93's description of the audio quality. There is a very noticeable difference.

Tested with:
iPhone 6S Plus, iOS 10.2.1
MacBook Pro 2016, macOS 10.12.3

Spotify Premium (320kbps)
No EQ settings
Wired and Bluetooth
Connect App 3.1
Firmware 1.2.9
Community Manager

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

Can anyone with an Android device confirm if the headset is still connecting to both the Call And Media Bluetooth profiles in Bluetooth settings?

What this to me is sounding like it's that for some reason the headset may be connecting to only the headset profile and not the stereo audio profile. Playing music through the HSP can be described as tinny, lack of bass, hollow, and other words I'm repeatedly seeing here.

I personally have an S7 Edge running 6.1 (awaiting 7.1 still) and I'm not hearing what you guys are hearing. My QC35 does still, and always has, connected properly to both Bluetooth profiles. Phone calls sound a little hollow (which is natural) and music always has the full dynamic range I'm used to.

If the iPhone doesn't allow the user to select the Bluetooth profiles separately, perhaps and Android user could chime in on their Bluetooth settings?
Community Manager

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

@remyc93 - A link to release notes are posted in the announcements section at the top of the wireless headphones board.

Sorry for the long link but I'm on mobile right now:

As of right now the potential to downgrade is unclear. We're awaiting additional information on this subject and we'll let you know when we know more.
Quiet Contributor

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

I am using 2 nexus (Android) tablets, nexus 7 2013 (6.0.1), and nexus 9 (7.1.1). My QC35 unfortunately updated to 1.2.9 which is when the audio quality dropped and the ANC functionality seems like it was cut by 50%. The ANC on my qc35 (after 1.2.9) is worse than the ANC on my qc25. The qc35 ANC was wonderful before the update (1.0.6). I can confirm that my qc35 is connected as both media audio and phone bluetooth profiles on both tablets (A2DP & HSP). I don't have any bluetooth problems with the 1.2.9 fw update, just the audio and ANC have dropped in quality. I have not changed anything else with my setup. These problems happened right after the fw update which leads me to believe the problem is with the new fw. I hope a solution can be found soon. I also second the idea of being able to select how much ANC via the connect app, the same way it can already be done with the qc30.

Quiet Contributor

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

 I just did some more extensive testing and I think I have an explanation for the drop in audio quality. I tried listening to the same song, at the same volume with the qc35 paired as phone and music (HSP & A2DP) then disabled phone (HSP) and only enabled A2DP. When paired as phone and music, the audio was bad, really bad. But when I set bluetooth to music (A2DP) only, the audio quality was excellent (1.0.6 good). This tells me the qc35 with fw 1.2.9 is selecting phone (HSP) audio by default when listening to music on any device.


However, ANC is still bad even when not connected to a device. I believe the drop in ANC performance is a separate issue.


Hope this helps! (P.S. I don't have any Apple devices)

Quiet Contributor

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

Confirmed that qc35 is selecting HSP as default bluetooth profile. Disabling HSP and only enabling A2DP on tablet solves the poor audio problem.

Animated Arbiter

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

Note: I am the same person as Bricked35, but I forgot my login (use fake email) so this is my new username. This should be an easy fix for Bose engineers. This explains a lot of the issues other people are having with the new firmware. All Bose needs to do is keep current 1.2.9 software, but set qc35 to use A2DP by default. 


This also explains seemingly unrelated issues like calls don't come through headphones, or can't connect with Sony/gaming consoles because gaming consoles use A2DP by default. 


Just as a reminder, noise cancelling (ANC) still isn't working at previous levels; and I don't think ANC has to do with Bluetooth settings.

Quiet Contributor

Re: Audio Quality Concerns Since Bose Connect/QC35 1.2.9 Update

Well weird things have happened now!
It has begun working all of a sudden (sort of)! Woke up after a sleep tried them again for my morning bus run and the bass is back on point.
Mid-range is good but missing the top ends which is the treble.
The treble however is quite sharp and a tad flat, quite bad at high volumes. I do think there has been a volume limit increase of some sort. At my normal levels it sounds slightly rough in comparison to before.
Yet, It doesn't feel compressed anymore.
It definitely is different as of the update.

This is via Bluetooth. I connected the cable first before trying Bluetooth.

On the ANC front, I'm not sure, something feels not as submersed. I hear more bus noises and announcements, same for the metro.
Maybe it cancels noise differently when on A2DP; I always feel something different when I connect to a call. Maybe that's why it feels slightly down on power?

Don't mean to fill the post with crap. Just keeping you posted! When I'm free tomorrow I will do some tests with my PC between Bluetooth modes.