Voltage drop when smart switch is toggled.

Thread Starter


Joined Dec 11, 2021
I have never posted here before but found this forum from searching to an answer to my problem (i still haven’t found one yet). I’m hoping someone who has more knowledge than me in electrical. I went to school for Chemical engineering and the only electrical class we took was physics 2 which was mainly all about circuits and fields (Theory nothing practical). I have some experience in changing generic light switches and plugs and I know how to troubleshoot but I don’t know that much about electrical wiring besides what “YouTube University“ has taught me.

My problem is that I bought a house in March of 2021 that was built in the 1970’s and I don’t think the wiring has ever been updated. The house also does not seem to have any ground installed. I replaced a light switch because the previous one broke (nothing electrical). I bought and installed a C by GE smart switch. After installing I noticed a buzz coming from the ceiling fan. I did some trouble shooting a found a few things out:
  1. The sound only happens when the fan is on
  2. The light flickers when fan is not on max speed but it can be fine when the fan is off(with Inconsistent flickering)
  3. Points->load-lineload-neutralline-neutral
    Switch on ->66123124
    Switch off ->1231230

The switch also does not require a neutral wire so I have the neutrals of the load and line tied off together.

I also previously replaced another switch with the same C by GE and began to notice a buzzing sound in the ceiling over time. After 2 months the sound became louder so I removed the switch which stopped the buzzing sound. After going into the attic I found the source of the sound (It seems to be the source anyway). The device still gives off a soft electrical buzzing sound even after removing the switch but because I have no idea what the device is I left it alone. (Unknown device causing sound in picture below)9162BED2-388B-4A3C-B084-D85CB5450EE8.jpegB1602F29-B9BA-4CB1-A8C9-59260B5D8818.jpeg3BDF90CF-E30B-4998-9BC0-9E43834F639F.jpeg
I am at a loss for what are causing these issues because generic switches work just fine. Any help would be appreciated.


Joined Jun 22, 2012
The gold looking device is a Transformer, which will buzz when mains is applied, if you're in USA then it will buzz at 60Hz,.