Rescently, there has been a funny odor in my finished basement. i checked the carpet (there is a 1/2 inch underpad over concrete) and found it to be quite damp but only underneath of our hide-a-bed. I pulled back the carpet and underpad and found the concrete to be damp. Also, where some of the metal from the hide-a-bed touched the carpet, I found rust. is it possible that there is a crack in my foundation. The dampness does not appear anywhere else. This is the first time that we've noticed this. We do have central air and it is much cooler in the basement.
Answer:
If the hide-a-bed from is solid from the mattress to the floor, this could be only condensation due to a complete lack of ventilation. I'd want to put bricks under the frame in strategic places to see if that helps before starting to dismantle walls to pinpoint where the water is coming from.