We have an old house with a neat mechanical doorbell. The bell is one of the hammer/bell kinds. I've installed 2 video doorbells which have been powered by this just fine. I tried to add a 3rd but it adds just too much power draw leading to a constant hum from the transformer and a low level ring from the bell. I read on another forum that adding a 0.5-2 W resistor in parallel with the bell will eliminate this problem without causing damage to the transformer. Would this work? Any alternatives? I'm trying not to have to replace the mechanical doorbell part of the system. It's neat and old and fits the house. Thank you.