Low Headphone Audio since IOS 26.4.2 Upgrade, is there and will there be a fix?

System Software Updates can sometimes have unexpected consequences - such as changes in audio levels - as encountered by yourself. While device settings appear as expected and respond the adjustment, something isn't right. A systematic sequence of troubleshooting will often clear the underlying problem.

As already advised by Jeff Donald, at the time of writing iPadOS 26.6 is current. If you haven't yet updated to the most recent version of iPadOS, you should do so:

Update iPadOS - Apple Support

If your iPad is not operating as expected, try a forced-restart - as this will often clear an isolated or post-update software issue:

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

If the problem persists after performing the restart, it may be necessary to reset your iPad settings. While this reset will not cause any loss of data, as a precaution, it is always wise to ensure that you have a current iCloud or iTunes backup before performing the reset:

How to back up your iPhone, iPad, and iPod touch - Apple Support

When you are happy to proceed, you can perform the reset from iPad settings:

Settings > General > Transfer or Reset iPad > Reset > Reset All Settings

If the problem still doesn’t clear, the next step is to reset the iPad to factory settings:

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

Otherwise, you would be well advised to seek assistance directly from Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page. Alternatively and perhaps easier, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:

https://apps.apple.com/app/apple-support/id1130498044

You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to hands-on test and assess the iPad and your Headphones. Here, if a hardware issue is identified, you'll be in the best possible place to explore your available options:

Genius Bar Reservation and Apple Support Options - Apple

Having followed the suggested troubleshooting steps without success, it is in you own best interest to continue with the recommended process - and seek assistance directly from Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page. Alternatively you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:

https://apps.apple.com/app/apple-support/id1130498044

You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to hands-on test and assess the iPad and your Headphones. To reiterate, if a hardware issue is identified, you'll be in the best possible place to explore your available options:

Genius Bar Reservation and Apple Support Options - Apple

Your assertion that the problem is with iPadOS, and not your iPad, is difficult to prove. If the problem was a software issue, we would see many such reports within the Apple Support Community. At present, there is no such evidence.

However, if you believe that you have identified an OS bug, Apple invites submission of Bug Reports via its Product Feedback Portal. For iPad and iPadOS:

Feedback - iPad - Apple

If submitting a Bug Report, please ensure that you include details of your iPad model and installed version of iPadOS within the body-text of your report. Don't rely upon the pick-list alone - as this rarely includes the current versions.

ConcernedDadofAudiofile wrote:

The iOS is at 26.6. The Headset is Bose Quiet Comfort. We also had an older iPad that we ran a test on which the sound was working as expected and as soon as we upgraded to the latest 26.6, it lost its former loudness. We have determined through testing various iOS devices that this issue was introduced as early as iOS 26.4.2. The sound degradation is especially noticeable with online videos. The issue is that, lets say you play a video on youtube website, before your volume would go to 10, (scale from 1-10), and now it is 7. Functionality is there just volume has been lost.

Perhaps consider that the Bose QC has its own active internal amplifier and noise cancelling circuitry with an independent set of audio controls. While the iPad is an audio source, the iPad does not directly drive the headphone's transducers.

Lower than expected audio can manifest in passive headphones that have incorrect impedance matching with the source. Passive wired EarPods and Headphones that are designed for use with tablet computers and mobile phones typically have higher input impedance than those designed for use with HiFi and other audio systems - the latter typically being designed for 8 ohm audio sources.

OK, iOS 26.4.2 is any months old. The current iOS is 26.6. What exactly happens when you update to iOS 26.6? What headphones are you using? Are they Apple headphones?

You said you tested several other brands. Did you test with any Apple or Beats branded headphones?