Good to know that maybe circulating the air in the house helps. I may be able to program that into my existing thermostat.
No bonus room and I've confirmed there are no disconnects in the system. Looking at the system, it looks like they did a piss poor taping job of the leaks and gaps also so I'll definitely start there. Should I at least attempt to seal the cold air returns better?
Yes, open concept main area that opens into the stairwell down to the garage man door and basement. I'm looking into sealing the garage man door as well.
Stupidity is a disease we all have, it's like a form of brain herpes. Outbreaks will occasionally occur.