I completed a job at an home service company. Upon arrival, the system was cooling, but the master room was not getting enough air. I checked the ductwork in the attic and found everything nice and sealed. I inspected the pressure and temps and everything was looking good. The supply plenum was leaking some air, so I added tape and mastic to seal it up. The filter was filthy dirty, so I replaced and cleaned the frame. I also put the blower speed to speed 5, which is the max speed. The customer was starting to get more air in the room before I left. The customer was also inquiring about price for running another supply to that return as he thinks that it needs another supply vent. I collected the $79 service fee customer paid with card.