iPhone 12SE randomly dropping the volume and raising it again.

You may try some of these steps, please check after each step...

1. Remove any protective films or cases that might block/activate the button or switch. · Check for debris or dirt around the button or switch and clean with ... If a button or switch isn't working on your iPhone or iPad
2. See the pic below which shows what I have observed and is self-explanatory.
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3. Try change with buttons [Disabled]
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4. Sometimes, a simple restart can resolve temporary software glitches. Turn off your iPhone, wait for a few seconds, and then turn it back on.
   1. Restart the device. That's it.
   2. Still not solved --> Force restart iPhone - Apple Support
5. Reset Network Settings: Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings: Only network settings are removed.
   1. When you reset network settings, previously used networks and VPN settings that weren’t installed by a configuration profile or mobile device management (MDM) are removed. Wi-Fi is turned off and then back on, disconnecting you from any network you’re on. The Wi-Fi and Ask to Join Networks settings remain turned on.
   2. To remove VPN settings installed by a configuration profile, go to Settings > General > Profiles & Device Management, select the configuration profile, then tap Remove Profile. This also removes other settings and accounts provided by the profile. See Install or remove configuration profiles on iPhone in this guide.
   3. To remove network settings installed by MDM, go to Settings > General > Profiles & Device Management, select the management, then tap Remove Management. This also removes other settings and certificates provided by MDM. See “Mobile device management (MDM)” in the iOS Deployment Reference.
   4. Reset your Network Settings. Tap Settings > General > Reset > Reset Network Settings. This also resets Wi-Fi networks and passwords, cellular settings, and VPN and APN settings that you've used before.
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6. If the issue persists, you can try resetting all settings on your iPhone. This will not erase your data but will reset all personalized settings to their default values. Go to Settings > General > Transfer & Reset > Reset > Reset All Settings and confirm the action. Note that you will need to reconfigure your settings afterward. All settings—including network settings, the keyboard dictionary, the Home screen layout, location settings, privacy settings, and Apple Pay cards—are removed or reset to their defaults. No data or media are deleted.
   1. Reset All Settings: Return iPhone settings to their defaults - Apple Support:- Return iPhone settings to their defaults
   2. You can return settings to their defaults without erasing your content.
   3. If you want to save your settings, back up your iPhone before returning them to their defaults. For example, if you’re trying to solve a problem but returning settings to their defaults doesn’t help, you might want to restore your previous settings from a backup.
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7. Make sure you have the latest updates installed.
   1. Update Over-the-Air (OTA) —> Update your iPhone or iPad - Apple Support (IN)
   2. Update using iTunes/Finder —> Update your iPhone, iPad, or iPod touch - Apple Support (IN)

If none of the above steps resolve the issue, it is recommended to reach out to Apple Support or visit an authorized service center for further assistance. They can provide specific guidance based on your device model and iOS version.

I don’t think Sravenkrva read your post… the issue is not that the volume buttons are non responsive, but that something internally is lowering the sound output without affecting the volume level indicated by the device.

I have the exact same issue and it has been my constant companion for years now (I periodically look it up to see if anyone has any actual information about this issue, but I usually only find a bunch of useless answers that aren’t addressing the issue that you and I and many others experience). I suspect that this is an automatic feature in order to limit how hard the device is working in some fashion, throttling the audio when the battery is low or when the device starts to overheat (though why it would choose to throttle audio output instead of, say, video processing resolution, or crashing the webpage, or having a banner that pops up and says something helpful and explanatory, who knows?). It can also be triggered on my phone by changing apps quickly or interacting with a notification banner (even just swiping it away), and the inconsistency of the audio drop happening under those circumstances indicates to me that it’s not an audio drop because of a silent notification or something else. I suspect that it is related to the phone battery needing replacement—I also have an iPhone 12 (mine’s a mini), and I have never had my battery replaced. Which is to say, it is not in good condition. But for now, all I can say is that you are not alone, and the mystery continues.

I appreciate this. It did not help, and I’ve already tried several of these options before 😅 the nearest Apple Store is pretty far away so I suppose I’ll just deal until later when I make it to the city.