new solid maple floor noise
Squeaking floors are always caused by differential movement of the hardwood over the substrate. This can be caused by a variety of factors, including inadequate support, improper installation of the substrate, improper installation of the hardwood, differential moisture conditions between the bottom and top of the wood, and a few less common problems.
As noted, installation of hardwood over concrete is problematic because the concrete tends to wick moisture upwards, creating a condition where the bottom of the hardwood is at a higher moisture content than the bottom of the hardwood, causing the potential for warping of the hardwood. The same issues can cause problems with the substrate, especially if the wrong type of plywood was used.
Since you seem to indicate that the floor was newly installed, I suggest you discuss this issue with the installer. Ask to see their moisture test on the concrete, and determine exactly what steps they took to control moisture wicking through the concrete.