We developed a strong sulfur smell from our master bathroom faucet not long after installing a new moen faucet and flexable supply lines. It is only on the cold side, only on this one faucet in the house, and does not affect the shower in the same room. The only other change is shortly before, we had a plumber install a valve out by our deck. I noticed he tapped off the line just before our bathroom. The funny thing is that my uncle who lives an hour away installed a new moen kitchen faucet and now has this same strange thing. His house is four years old!! We’ve had an artesian well for over 25 years and never had this problem. Please help!! thank you.