My house is about 6 months old, and lately we have started noticing that as we walk through the house, mostly on the 2nd level, the floorboards along the interior walls make a cracking/popping sound. What would cause this? Is the problem with the floorboard, or with the wall framing? I actually had the framing contractor come back about 3 months after we moved in, he pulled up the carpet in one room and put some shims in between the baseboard and the floorboard. The sound went away for a couple months but is now back the same that it was before... Am I ever going to get this to stop? Thanks for any input.

I don't have a clue about the quality of construction or materials bit lets assue everything was done correctly. A new house settles and the lumber dries out. The home soon stabilizes but it can take a year, that's why most drywallers will do a call back within a year to fix nail pops. I would keep calling the builder just to let him know you have not dropped the matter and let him off the hook.

Sounds like the floor is slightly separated from the joists. Not uncommon when a house if framed in the summer and then winter contracts the floor away from the joists. Have the builder pull the carpet back and after finding where it is popping and cracking, screw the floor to the joists.