I am using the ISY 994i and up until a few weeks ago everything was working great. Now if I turn lights on or off other lights that are on will flash on and off. I have several motion sensors to control outside lights and when those are activated and the light outside comes on and then turns off after programmed setting in ISY 994 some of my inside lights that are on will flash on and off then back to on. Do I have a bunch of switches going bad? All my switches are the Insteon togglelinc type. Anyone have an idea what is happening. Thamks

Do you notice if it's always the same inside lights that turn on, off and then back on?

Have the motion sensor batteries been replaced recently? Maybe something to try.

Its not just the motion sensor. I have a couple insteon multi button remotes that do the same thing just randomly flashing some lights on and off. I have two togglelinc switches for my hall light for stairs going upstairs and when I turn those two on or off they also make other lights flash on and off. This is all random. I have not made any changes to the programming in the ISY 994I for a couple years, this just started a few weeks ago. I have checked all the settings in the 994 and nothing looks different. Are all my togglelinc switches failin? They were all purchased and installed in the same year or so, 10 - 12 years ago

More checking I have found that it is three togglelinc switches that are doing the on/off flashing when something else has been turned on or off. It is random and not all the time.

Have you tried a factory reset and device restore on these togglincs?

@dennisric , the "flashing" sounds like a noise and/or power supply filtering problem (capacitor dying).

1. Are your togglelincs on the same circuit?

2. Have you changed the loads on the switches?

3. Any recent issues with the utility transformer/neutral line to the house? (or other electrical work).

I agree that a simple reset/restore is easy and prudent. If that doesn't work you might try swapping one device out to see if that corrects the problem. The togglelincs are ~10 years old or more. Very possible that the power supply's are starting to have issues.