Video inspection of underground air ducts due to homeowner reporting a smell from some of the vents. There was Stan ding water in many of the vents. Ran the bathtub and could see water rising in vents which means bathtub drain is leaking under slab and getting into ducts. Homeowner needs a plumber to repair leaking drain, then recommend spray lining ducts with Duct Armor to encapsulate contaminated ducts.