Homeowner states that a day ago he was running water from the washer box down the drain and went to the basement and saw the wood had water marks that were very fresh and believed it was from the washer box drain and called us to see if that was the case. When I arrived homeowner showed me what he did and we went to the area in basement and the water marks were a lot closer to the kitchen sink drain then the washer box drain and I informed the homeowner. He ran the kitchen sink and the washer box hot side and I could not see any leaks or anything that could be causing the leak. I informed the homeowner to use a water restoration company to so they can attempt to find the leak since they have moisture meters and infrared cameras. Homeowner understands and will contact a company and unfortunately there is no signs of a drain or water leak so I cannot do anything at this moment.