New construction in Colorado, house is just over two years old now. This is a two story house with an "office" on the first floor at the front of the house. I work out of my house and use this room as my office. I'm not exactly sure when this started, but I've noticed that when I walk in to the room, I hear a lot of crackling noises coming from the outside wall. I can also push lightly on the wall and it will make all sorts of crackling noises. Once I have pushed on it, it's like I'm releasing some pressure and it won't crackle for a while.

I have no nail pops and no cracks in any of the walls. I've gone outside and looked at the foundation and there are no cracks anywhere along the foundation.

Any idea what might be going on? Just regular settling? Temperature differences between the inside and outside of the house?

I am trying to decide if there is anything that I should do about this, or if it is completely normal.

Normal new construction noise is from wood parts expanding and contracting, and sometimes curing if it was too new when first built.
It can depend on the temp and humidity during the period it was built, how the wood was stored, whether or not it was open to the elements... basically anything that affected it's dryness and age when fastened to other wood.
Also, you don't mention going into a basement. Is it on a slab? Are the interior walls typical drywall, taped? Or skimcoated?
Wood floors? Laminate, engineered, or solid? Subfloor panels too close together? Exterior sheathing same? (No room for expansion)
You never know if a newbie was working that day.
etc
If neighbors were built at the same time, as them.

Wow. I don't have answers to all of those questions, but I do have some answers.

If how they're building them now is any indication, then the wood is stored at the construction location. They seem to just pour the foundation and deliver the wood. Then, the construction begins. Of course the company doing the construction now is just the newest in the neighborhood. The company that built ours was two companies ago. Construction on this house was done between October and January.

Basement, not slab.

Interior walls are drywall. I think that they were taped, though I can't remember. I'll have to see if I can find some pictures. We were living out of state while the house was being built. The walls are textured, though I doubt that has anything to do with it.

The floor in the office is carpeted. I should also mention that there's one area of the office floor that pops every once in a while, when walked over. I'm hoping that I can just figure out where that's coming from and either nail the area down, or put a shim in.

I'm not sure about the subfloor. I don't know what the spacing should be. We're also having some issues with the master bed and bathroom floors. When walking across the bedroom floor, you can hear popping noises coming from under the shower, as well as a couple of noises along the west wall in the bedroom. Our bedroom is west facing, and it only happens when the sun comes over the top of the house. It's the biggest problem mid to late afternoon. The builder tried putting foam under the shower base, but it didn't make a whole lot of difference. I'm still waiting on them to make good on fixing that.

The house is nice, and it's in a good neighborhood, but there are so many little niggling issues that are annoying me and the builder has been less than responsive. Stuff that will likely never get fixed unless I shell out to fix it myself. As for wall noises, we only get them from the office. All of the other walls are pretty much silent.