Hi, we have electric blinds in the bedrooms in our house and I can hear clicks and see flickers on tv's, lights, speakers, etc when they start or stop moving. This morning I was on my laptop with my headphones over my head, which are connected to my external usb sund card btw, someone in my house woke up started lifting the blinds and I hear a click through my headphones with the laptop charging, I disconnected the charger from the laptop and waited for the blind to stop moving and I still heard the click! The only possible way was through the ethernet cable. What causes this click to be heard/flicker to be seen every time the motor starts or stops moving through almost every electronic device in the house?

 

Without actually seeing the controlling circuit for the blinds it's hard to say but for example if the blinds use any relays with their motor(s) you could be hearing RFI (Radio Frequency Interference) interference. Think of it as transmitted noise independent of the power lines. Again, hard to call without actually seeing a schematic of the controlling circuit and actually hearing the clicks or noise. Do the blinds use a RC (Remote Control) and if so what type? Anyway, my guess is relay or motor noise being transmitted.

Ron

 

What causes this click to be heard/flicker to be seen

It's called "interference" and arises from electromagnetic pulses due to motor switch-off (back-emf spikes when current through an inductor tries to decay). The motors of the blinds, or their controlling circuits, obviously have no/inadequate suppression components.