The space is tight to get a good shot of the whole unit in one frame, but below it is the return air box that's a also platform raised off the floor.
The installing dealer sent someone out back and redid that sloppy transition duct piece. They also adjusted the dip switches and said it was the air handler setting was for 5 tons of airflow. He did some measurements and didn't feel like the existing duct work being insufficient was an issue. Checked refrigerant levels to airflow and felt it was good. He was here about half the day.
Much quieter now, cools the place down good and gets sufficient airflow until the last part of the zone. I think the biggest issue was the air handler setting. Really amazing just how much louder it was originally. I was doing some comparisons to some other houses (even got a db meter) to compare noise, and I think everything in terms of vent noise is where it should be.
I think my problem was I got a Friday install. Hopefully this ends the issue, he said feel free to reach out if I had any concerns and needed them back out.
