Patching and Plastering - Hairline cracks at joints

I'm in the process of finishing my basement and have recently finished the drywalling, complete with knockdown texture and paint. As I am a budding DIYer, I did the drywall mudding and taping myself. I used paper tape on some joints and the perforated self adhesive tape on others. I believe I followed all the right techniques and up until the other day, I was very satisfied with the job.

Here in SE Wisconsin, we've been hit with record rainfalls and therefore I've had the dehumidifier running constantly in the basement. Along one long exterior basement wall, I noticed yesterday that there are several hairline cracks at the joints.

For one, I'm not sure how this is occurring. Could it have something to do with the excessive moisture?

My main question is how do I repair this? I can't tell if the crack transfers through the tape. I could open the cracks up and fill in with mud, resand, and refinish....but would that be the right approach?

Can someone fill me in here on what I need to do?
How to repair the crack in a way that will keep it from coming back?
How to match the texturing?

the cracks could come from a couple different reasons. Most likely you probably put too much mud over the tape or didn't pre fill your joints before taping. I could be wrong but a lot of time thats the problem. If they are truley hairline on the textured part then you might be able to caulk them. That way you wont have to mess around with re texture. on the walls make sure no tape is loose. Cut away any loose material. Re tape with all purpose mud and paper tape.

Usually when you have cracks in the drywall joints it is from somthing moving behind the wall such as framing, or the ground is shifting and causing the foundation to move. Water could be the cause of this. If it is real humid, then the wood is swelling and causing cracks. I would wait untill everything dried out before trying to fix cracks.

Definately sounds like movement. Go to the areas that have cracks and push on the drywall in several places on either side of the joint while looking closely at the crack to see if you can detect movement. If you can see movement then add addtional screws to see if you can tighten things up.

If it is a furred out concrete or block wall, you may have to try to secure the furring lumber better to the wall.

I experienced this very cracking on a hotel job where the old drywall was glued to the block walls. Once we sprayed on texture and let it dry, we got hairline cracks. Additional fasteners solved the problem.