iPhone 13 Pro Max - restarts every 3 mins / Sensor 0x800

On previous model iPhones the errors are more specific; in particular there are two sensors known to fail on the charging port assembly; one is labelled mic1, but it's not clear exactly what the sensor associated with the microphone does. It may indeed be possible for the sensor to fail but the microphone works fine.

Secondly, there's another sensor called PRS0 that has to do with the barometric vent at the bottom of the phone; PRS0 is commonly understood to be a reference to a pressure sensor.

However, as of the iPhone 13 model, the distinction between those sensors is gone and you only get the indicator that the charging port is bad. In your case, for example, if the PRS0 sensor has died then sure your charging port and microphone will still work fine while the phone lives it its eternal boot loop.

As Mr. Lex has already suggested, replacing the charging port will almost certainly fix the problem. I have replaced the charging port assembly on an iPhone X due to that sensor and it did indeed resolve the issue.

I have the same problem with the 0x800 sensor. I had dropped my phone and there were two cables behind the broken glass that poke just out of the shielding behind the phone. If its the backglass facing towards you with the cameras on the top its to the bottom right. I had been touching those wires and one of them broke off lol. My mic doesn't work when it's connected to speakerphone. Same thing with voice memo, however recording using the camera it picks up my mic. The proximity sensor still works too and the charger is fine as well.

I will replace the charger assembly but would be open to possible answers.