Glade to be here and thanks for the quick response.
1. Yes...I can manually operate the switches by physically tapping switch
2. Just using a couple of standard X10 rf switches...no activehome involved.
3. Not sure what type...they are standard rocker dimmer switches purchased from X10 about 5 or 6 years ago. I have 4 installed and all were working up till couple of weeks ago. I have two lamps ... one plugged into the transceiver module and that works. I also have the other lamp plugged into a separate outlet module and that works. So it just seems to affect the hardwired light switches. I wouldn't think they could all be bad at the same time. Why would line noise only affect only the light switces and not the outlet based lamps?
I tried moving the transceiver module to different outlets but only the wall outlet modules work. Any other suggestions would be greatly appreciated.
danh_d,
That definitely narrows down the field.
To answer your question on noise - It will have an affect on all of your devices, but the degree to which the devices are affected depends on the location of the noise source. Both X10 signals and noise diminish as they travel down your electrical wiring. The further the distance from the transmitter, the lower the signal (or noise).
From your description, your lamp modules are physically close to your transceiver (one plugged directly in - this should always work). You wired switches could be on another circuit, or additionally, on the opposite electrical phase. If so, these would be much more susceptible to a noise source in the vicinity.
If you have an outlet that you know is on the same circuit as one of your switches, you could move your transceiver there to verify that the switch still functions. This won't correct anything, but will give you one of those "warm fuzzies" that nothing has changed with the laws of physics.
Past that, I believe you have a noise or signal sucker between your transceiver and your Switches. If you can't find it by inspection (cell phone charger, laptop charger, etc), you'll need to start popping your circuit breakers to try to isolate the "problem" device. While you're performing this (it can be rather painful), you should really map your electrical circuits and note the installed devices. This can pay huge dividends down the road when something similar happens again.
The forum has a "general troubleshooting" thread located here :
X10 Issues? Please Read This FirstHave a look at the sections on Noise, Signal Suckers, Mapping your circuits, and Phase coupling.
Speaking of phase coupling, you didn't mention whether you had a passive coupler or active repeater installed? If you don't, you might want to consider this. However, I would suggest that you determine the source of the problem first.
Let us know how things are progressing,
Boiler