I'm on the 6, two years older than that, and experience lag but never a single stutter on anything audio related. It sounds like an issue that a reset or reins

I'm on the 6, two years older than that, and experience lag but never a single stutter on anything audio related. It sounds like an issue that a reset or reinstall may fix. I'd be similarly pissed off like you if even my much older phone did that.