Been having this issue too.
if I swipe the volume down in control center from example 40% to 0%, it pops back up to some in between point once the dial animation bounces back.
im thinking this is intentional design if you swipe it too quickly. It’s trying to predict where you might actually want the volume to be at based on your typical volume setting. I usually keep my volume low, under 10% and occasionally turn it up. Then I get in bed and I swipe it to 0% too quickly, it seems to auto correct my volume to a more common 10% range instead of completely silent. It’s basically like predictive text or auto correction because it only happens when I swipe it really quick.
if I make a very precise volume adjustment, then I don’t see it happen.
and I think it’s even more likely to correct your volume if you currently have an active playback happening in your control center. Like if I’ve recently had YouTube playing something in the background, control center has the mini controls for it. So I think it’s trying to predict what volume you need in that moment based on what else you’re doing on the phone and how quickly you swipe the volume control up or down.
It’s assuming you don’t want it fully muted in that moment that you rapidly swiped the volume down. Like when it autocorrects your swipe texting. Same idea, so I’m assuming it’s intentional.
Try just swiping it slowly and precisely, and closing any background apps that play music or video too.
When I change my volume slowly then it doesn’t happen. Only when I swipe it fast. It’s dumb, but its the only explanation for why it’s not been fixed in years. The smartphones are trying too hard to add predictive features and functions to correct or assist in ways we don’t really need.
That’s just my theory. Hope I’m wrong or they at least acknowledge we don’t want this feature.