What is the problem with my HVAC system? Air flow better out of 2 of the vents. on 2005 Ford Explorer

The 2 center vents blow great. The 2 nearest the doors blow less but the passenger side vent near the door blows better than the driver's side. Also, the blower does not increase when MAX A/C is turned on. Replaced the blower resistor but no change.

Asked by for the 2005 Ford Explorer