iPhone plays media out loud after putting AirPods in case

I've recently started having an issue where my AirPods (rightly) pause whatever media is playing from my iPhone because of the automatic ear detection, but once I put the AirPods back in their case, the media starts playing again from my iPhone speaker. This has been going on for maybe a year or so. The only advice I've seen online is to turn off automatic ear detection, but this is not the cause of the issue, only a way to circumvent it.

iPhone 13 Pro

AirPods 4