recorded iPhone video volume level drops when recording and playing back loud sounds

Hello,

I recently purchased an iPhone SE (from Japan) and realised that the volume on videos tends to suddenly drop.

So far I've found that it only drops when the volume in the video is loud.

An example of this is on an amusement park ride, the volume started out normal, however at the point the ride drops and people start screaming, the video plays as per normal but the volume is suddenly lowered drastically, to the point I can barely hear anything.

Another example is when I recorded a short clip of a local festival and when I played it back later, I could barely hear a thing.
It seems like it only happens on videos recorded with the phone. Other videos I transferred over from my old phone play normally, even the loud ones.

I've checked that my phone wasn't on silent and the volume was maxed.

I've also checked that I didn't turn on sound limiting and soundcheck was off.

This did not happen on my previous phone, an iPhone 5S.

Is there any way to resolve this?