This issue seems to have healed itself, but I want to present it for possible discussion.
What Happened: Several nights ago, several LED bulbs were flickering and pulsing; each of them on dimmers.
The Odd Part: Individual bulbs were doing the flickering, even if they were in a three- or four-lamp fixture. A three-bulb floor lamp might have one flickering. One four-bulb fixture had two flickering, the other only one. A further odd part: two different types of dimmer, two manufacturers. Ceiling fixtures on Inovelli blue series; floor lamps on Lutron plug-ins.
The Bulbs Involved: GE clear 60W-equivalent 2700K A19. No others.
I shut everything off, waited a while, turned them back on. Same flickering from the same bulbs. I shut down for the night.
Self-healing: The next day, and since, the lamps have been as stable as they have been for the last several years.
What level was the dimmer set at? Very low? Maybe your incoming line voltage was low at that time, and that put it under the threshold of the some of the bulbs but not others.
I have a similar situation where one bulb starts doing that occasionally, and if I bump up the dimmer a bit it stops. Next night (at previous level) it doesn't flicker.
I played with the various dimming levels and the same bulbs were flickering, regardless of the levels. Also, similar dimmers running different flavors of LED lights were behaving themselves. I even moved one of the Lutron dimmers from where the lights were steady into my bedroom to see if it was the dimmer failing. The problem followed the bulb and not the dimmer.
As stated, this was several days ago, and all of the lights are working perfectly and have been since that one night.
Some sort of weird electrical issue from the power company
Poltergeist - you should get out of the house and burn it down just to be safe!
That truly is a strange one. Since it affected two fixtures on two different dimmers, I'd bet it was #1 above. Maybe some of those LED bulbs are more susceptible to incoming power fluctuations than the others? If it happens again, you could try putting a voltmeter on the 120VAC power at a free outlet in the house (please only try this if you can do so safely.) If you have a Kill-A-Watt device, that would be a very easy and safe way to look at both the voltage and frequency of your incoming power.
Once in while LED bulbs were dying but unfortunately not like black and white. Recently few about 5 years old LED bulbs started to flicker randomly. It was very hard to figure out which one in a set of 4 was about to die because by Murphy law when you watching these lights everything is perfectly fine.
