It only worked some of the time, so the signal strength needed to be boosted, also around Christmas other people in the neighborhood also started using X10 to turn their Christmas lights on and off, it looked like things were going on and off on their own around the house when it was the signal from the neighbors X10 signal being sent into
our house wiring.
Electrical Noise will cause X10 problems - see debugging tips
If you use X10, you will inevitably experience some of the problems described right here.
X10 COMMUNICATIONS PROBLEMS
X10 Debugging Tips
This unit slips over the neutral wire feed entering the house shown in picture below. It senses the presence of X10 signals and generates an offsetting voltage signal to neutralize it. At the same time it acts as a passive (non-amplified) signal coupler and allows X10 signals to travel between phases within the home.
Whole-House Blocking Coupler CAN BE BOUGHT RIGHT HERE