Xpantastic!

I have had a similar flickering light on my fridge for year. I think it is not serious in case of an 
Xpander either. That's probably a property of the bulb itself due to some manufacturing 
tolerances. Although stable LEDs were invented, they were not used in Xpanders, if I'm not 
wrong:

http://web.mit.edu/invent/n-pressreleases/n-press-04LMP.html