Inconsistent Timer Operation with WM100 via iOS

[xfm]

I have been controlling my outdoor lighting via X10 wall switch modules for many years via plug-in timer/controllers with no problems/issues whatsoever. Since getting the WM100, I've experienced numerous instances of individual lights not turning on as scheduled, lighting on schedule but not turning off, etc. I had started out with all 3 lights set on unit address 1 to turn on and off together, as I had for years. But one or more lights did not turn on or off consistently, so I changed each light to its own individual address, and after some experimenting with different combinations, I've achieved modest improvement. My current status is that the lights set on unit addresses 2 and 5 turn on and off as scheduled. The light on address 8 turns on per schedule but does not turn off. All 3 lights respond well to discrete on/off commands via the iOS app, so the signals are getting through OK. Any ideas?

[Tuicemen]

You don't say what type of light or its age is on unit 8.
Have you tried a different bulb? I've seen bulbs (even incandescent ones) as they age fail to turn off and replacing with a newer one fixed the issue.

[xfm]

You don't say what type of light or its age is on unit 8.
Have you tried a different bulb? I've seen bulbs (even incandescent ones) as they age fail to turn off and replacing with a newer one fixed the issue.

Thanks for the quick reply. Sorry for the omissions. It's an incandescent post lamp in front of my home. Switch is a standard single pole X10 switch over ten years old (maybe closer to 20). Looks just like a WS467, although it could be a predecessor if there is one. Can't see the model number and didn't want to pull the assembly out of the wall box unnecessarily. Worked like a charm with the M10A plug-in timer/controller for all of those years. Bulbs are new incandescent candelabra base bulbs (3) that were working flawlessly with the M10A timer. Also, I can command on/off manually with the WM100 iOS app and it works every time.

My front porch and rear porch lights are standard incandescent on similar wall switches (front porch is 3-way) and they are behaving as expected.

Don't know if it's relevant, but as part of my troubleshooting, I've set the on/off times of each of the 3 lights to be a couple of minutes apart to avoid any possible interference issues during on/off events.

[Tuicemen]

I had a new incandescent bulb which would turn on and off but if I left it on for any length of time it would fail to turn off with a single off send. This was due to a bad lose filament. This also cause so much noise on the line after a while all X10 devices on that circuit failed to work. You might wish to see what else is on that circuit that may be a possible noise or signal sucker if your changed timer setting still fail.

[Brian H]

Have you tried the MT10 in the same outlet the WM100 is now using? To eliminate possible power line issues.

[xfm]

Have you tried the MT10 in the same outlet the WM100 is now using? To eliminate possible power line issues.

I will try that. I was more focused on getting the WM100 plugged into a breaker branch that includes the outdoor circuits. The branch that the MT10 was plugged into is not in that sector. But I will try it tonight or tomorrow. I only want to test one potential fix at a time so if (when) successful I know where the fault was.

Thanks to all for the input and advice. Most appreciated. Much of my in-depth X10 experience has gotten hazy over time. I looked back and I did these installs in the 2000-2001 timeframe when I had a major renovation of front hall and front porch.