This weekend I noticed a brown line running through the ceiling in our dining room. It appears to be the outline of the drywall tape. At first I thought it was a leak since there is a bathroom above the dining room, but it only seems to be along the outline of the tape, which if it was a leak I thought it would spread unevenly. Can the drywall tape be bleeding through the paint? This seems to be the only area in the house where it is happening.