Hi, my newly installed re-milled solid walnut floors have been installed with a fully glued/nailed down construction over 3/4" plywood 2X8 planks. They are 5" beveled 5/8" thick planks. They have not yet been stained and finished. They had not only been acclimated on site for a month on stickers before installation, but they have been installed for several weeks now. Before they were sanded, I didn't notice creaking when I walked on them, and they felt solid. Now that they have been sanded, four of the boards creak/pop when stepped on near the widthwise seams of two planks. Will top nailing the areas fix the problem? Also, a few of the boards had to be edged down because they sat a little higher than others. Can that weaken the T&G because the wood surface is getting thin in those areas, and maybe cause the crackling sound? Other than that, the installation is beautiful.