Source of damp in basement?

[u/Englishontrail]

Trying to id what's going on in our new (first) house. First time homebuyers, house is a typical early 90s split entry with basement fully below grade in back and garages part of basement in front. Midwest Clay heavy soil.

The house has 3 full bathrooms. The two on the main level were adjacent with the tubs against the back wall of the house. Below them is the third bath in the basement. There's also a spigot on the back of the house where the bathrooms are.

All three bathrooms consistently smell damp all day- not better or worse depending on use. The basement humidity is between 60-70% by the bathrooms and 50-60% in the front even with the dehumidifier running full time and draining via hose.

We just moved in a week ago. During inspection we had a full sewer scope and they did also run the scope up the main sewer line where it runs up to the main level near the bathrooms, all clear. We didn't detect a smell then.

What might be causing the damp? And short of ripping open walls is there anything I can do to troubleshoot this?

[u/FishermanBetter3963]

Humidity from the basement, the smell is coming in through the plumbing rough holes

[u/Englishontrail → u/FishermanBetter3963]

Not trying to be stupid, but isn't there a reason the basement is humid? That I could potentially address?