A/C Temp issue right not as cold as left

[4.8isX5]

Hey guys...

So driving today with A/C on i noticed the right center vent is blowing lukewarm air... Leaned over put my hand on passenger side vent by door, same thing. Left center vent and drivers side vent by door is cold.

I've been told it may be the Final stage unit/resistor, but i did a search and looks like that is mainly for fan control issues (correct me if im wrong). All my functions on climate control panel seem to work fine, both settings set at 65F, i can control the fan from 1 to max. And seems like the direction controls work too (front window, face, and legs). My center vent dial is also set to 3 blue dots.

What can this be? I never had a chance to work on much of any a/c issues, previous cars was only a fan control board where fan got stuck on high and heat.

Thanks.