The soundproof box might be restricting airflow if your pressures aren't balanced right, and/or raising ambient temp due to the airflow restriction, try it without the box and see if the issue persist. if it does watch the dashboard and find out what blade is overheating and we can go from there , I'm in Waco I know the struggle too with temp fights, I gave up on soundproofing stuff years ago due to this , thankfully we aren't in Houston fighting humidity too.