Hey everyone

I am installing hardwood floors for the first time and I noticed a problem during prep.

I noticed some high spots in the sub-floor. Unfortunately when I pulled the sub floor it appears the beams are the actual problem. I don't think I can sand down the high spots on the plywood without adding stress to the sub-floor.

How should I go about shaving the beams and how much can I take off?

When I make sure its level should I just lay the sub-floor back down and check with a level?