So this June will mark a solid one year that it's been since my conversion of my home from seventy 60 watt incandescents over to 13 watt Sylvania Micro minis, and there has been only two incidences so far, I have a small home but like a lot of light as I am a night owl, 4  burn 24/7 and those have not acted up.  They have been great and I reallllly use them.  My electric bill dropped by around $20 a month give or take some.  So the two that acted up-

1. One of the three 150watt equiv giant Sylvania CFL's refused to start out in the garage when it was extremely cold this winter. It flickered and hissed. The next morning I was about to go get a replacement and low and behold it started right up so I cancelled the trip to Lowes home improvement and it has never acted up since!

2.  One 60 watt equiv in a bathroom ceiling fan vent/light combo above shower (fan buzzes and vibrates a lot) began strobing at I'd say 30HZ last night while I was showering and it scared the hell out of me.  It did it a few times lasting maybe 5-10 seconds each time then ran fine the rest of the night.  If I flicked it on and off it would act up once then normal.  I tightened it in the socket and that seemed to stop its misbehavior till today it did it again.  I then swapped it over to the other ceiling fan light combo that is a bit quieter and moved its bulb (same micro mini) over to the noisy fan. Both fans are Moens but one is more off balance motor it seems.  And nothing new has happened since so far its behaving!  I will keep posted!

Two weird occurrences, that seem to have rectified themselves, what could cause such issues?  I have a few spares but figured I'd try the swap before I replace the bathroom ones.  The garage one seems fine but is a bit "hissier" than its 2 other partners out there lol, but hasn't refused to light since that night. (Its partners, I have 3 150watt  equivalents out there never had same issue).

Thanks guys!

Mike

Off line voltage (likely lower tha normal) / condensation from the cold / combination of both

In the fan can be also bad solderings + vibration from the fan

Audible sudden HF hiss is a bad sign - the CFLs may be damaged allthough they are back up intact (maybe not for long ?)

Thanks Ash! Interesting.  The bathroom one is behaving perfectly now, possibly the solder joints were made weak by almost a year of heavy vibration but I swapped it over in time to allow it to run out it's normal life under less vibration. We'll see!

The hissing on cold may well be frozen electrolytic capacitor - it;s capacitance dropped, the circuit went into subharmonic oscillations, so the noise become audible.

The flicker in a fan may well have been only the lamp being loose in the socket (due to the vibrations). I would take some time and balance the fan, otherwise it would destroy any lamp (and I would even guess the fan itself or it's anchoring) there...

I have had a success with a Sylvania CF13EL Micromini bulb. Installed December 2009 in an enclosed two-lamp bathroom ceiling fixture.  Used about 2-4 hours a day cumulatively, about 6 starts a day.  started to blink August 2021 and retired from service.  No visible heat damage, no 'blackening' if the tube.  Yes, subjectively, the light was dimmer for the initial few minutes for the past couple of years.  But overall, the bulb has beat the expected life on the package by one year. I cannot say this of some of the other CFLs and even LEDs we've tried.  Hurray.  Does anybody want to do a forensic assessment of the bulb?