Air conditioning ?

[tim_ver]

I have a question on air conditioning, I have a high ceiling and it is at an angle the vent is in the ceiling and I have found an area in the bottom corner that looks like a water stain very small one and to the touch is dry. Is this from condensation from the air conditioner? How do I fix this issue? The other vents seem fine. Also this vent is in the same ceiling “about 4 feet away” as the intake. I took the vent off and found about 4-5 drops of water and some light mold on the edges of the vent frame.

[Rich]

I'm not thinking that it has much of anything to do with the air conditioner. I would suspect either...
1. Poor insulation between the duct and attic (open air)
2. A leak in your roof
3. Or some other problem with excessive humidity inside the home (have a humidifier?)

[tim_ver]

Well I do not the the walls in the house are airconditioned. I took off a outlet cover and felt cold air comming out. so maybe this is a issue? Also I just cleanned the filter "a lifetime one" I just rise in hot water and think maybe I did not dry it out enough and the water ened up there.

What do you think?

[Rich]

If it was dried enough it would probably only take 30 minutes or so with air going through it. And it might only add a couple % of humidity in the grand scheme.
Might want to check the duct for holes or disconnects. If it's pumping air into the attic space and wall space you may be condensing in that area and it's running down to the registers.
Without a full site walk I honestly don't know.