Im trying to install Home Legend floating click lock wood floor in my kitchen(about 75sqft). When I was working on the plywood subfloor I noticed that two of the joists had sunk a bit causing a depression(about 5/16'' at its deepest point). I used roofing shingles per many opinions on the internet and used a string to flatten out the depression as best as I could. I put down the underlayment and laid the floor. Now I have laid all the floor and here is my problem. When I walk on the floor I feel like it is giving a little bit as I step on it. Its not a lot, maybe 1/8'' give in the "squishiest" spots. This happens in random spots and is not specific to where the depression was. I only used strait planks and discarded the warped ones. So my question is... Is this normal for the floor to give a little and its all in my head? Or is the most likely cause that the subfloor still isnt level? Or is there some other possible cause Ive never heard of?