Flush it again?
All I can suggest is did you open up the faucet the last time you flushed your system with bleach? Use 1/2 cup of bleach in a gallon of water for each 40 gallons of fresh tank and let it sit for at least an hour. Then run that out the offending faucet and drain the system out of your low point drain. Refill and reflush until no smell/no bleach taste.