So, I got some nice oil canning sound that appear to be from the sheet metal blockers between the floor joists for my cold air returns. The joists are 2 x 12 - 16" o.c. and make the blockers do the oil can sound when you move weight from one joist to the next. Its compounded because the sound then travels up the wall and comes out the return vent in the room. I alleviated it some by unscrewing the metal blocker from one joist, prying it away slightly from the joist and subfloor and then sealing it with metal tape. There were cross bracing removed where the metal blockers went in so I tried to replace them but the joists still moved enough to make the metal pop.
Is there a better solution? So annoying. Brand new house, and full of annoyances like this. I am considering adding blocking between the joists closer than the current 8' spacing on the bracing to tie them together better. I also considered ripping out the metal blocking and using a piece of wood thats glued and screwed for the returns. Thoughts?