You know... for all the LED hype, these things are sure a pain in the a**, they're just like the old single wire lights, check bulbs 'til you find the culprit. Some 'progress' !
I wonder if anybody's actually calculated their 'power savings' vs. how many strings they've thrown away and re-bought, to say nothing of the recyclable glass, copper, and plastic in this 'offshore' junk.
Gimme' my old 2-wire 'screw-in's' ANYDAY, 1 -out, 1-in, fixed, ta-da !