When I first turn the cold water on at the kitchen faucet it stinks. If I let it run 20-30 seconds it clears up. This only happens at the kitchen sink and only with the cold water. I was told the ice maker hose to the frig could be stale and be sucking back to the faucet so we put a flow valve that will not allow back flow from the ice maker hose and we still have the smell. We have run bleach through the line to , no help. Any advice?

