Moose, your noisy relay Universal Module must be several years old, as Authinix upgraded the relay to a new quiet type back in 2018 or 2019. I purchased a UM506 directly from x10.com in Nov 2019, and the relay is quiet. If you replace your Universal Module with a new one, I suggest you purchase directly from x10.com, as other sellers might still be selling the old ones with a noisy relay.