Phone volume jumpscaring everyone

To clarify, not only is my iPhone 15 set to silent using the side switch, but I’ve also lowered the volume on the speakers to absolute 0.

Sometimes when playing videos from the web, twitter, YouTube, etc the video’s sound will begin playing at FULL BLAST from the phone’s speakers.

I would very much like not to be occasionally jump scared by my phone, and I hate being that guy with his speakers on full blast on the plane, or most importantly- waking our sleeping baby up. I always check to make sure volume is down before clicking links or videos but it still just jumps to high volume.

My phone has a case but it is not touching the volume buttons. I have updated all apps. My phone is running on current iOS.

Pls help.