Our home was built in 1995. We replaced the original faucets and countertop a year ago. Now we get a sewer smell from one of the sinks any time we turn the water on. It does not do it every time. We have tried cleaning the pipe via rooter. The city water department says the trap is burping. Only one sink does it and the other is only 4 feet away. Any idea what the problem might be? Trap, etc., are all the same as before. We also cleaned the overflow drain.