I bought two strips of the 12mm Diffused Flat Digital RGB LED Pixels (product #738). One strip is rocking it like a champ with the test code and making me a happy soze. However, the other one only turns on one LED, at the far end of the strand, whose connection seems at times spurious. When I wangle the cord lightly (pick up the pixel, move it up or down for visual inspection, nothing extreme), the color wanders all over the place, occasionally going dark, occasionally going full white, and any color in between.
When I test each strand individually with the test code, the well-behaved strand behaves as expected, and the poorly behaved strand does not light up at all.
FWIW, the working strand has the arrows (pointing in the right direction from the connection). The misbehaving strand has no such arrows molded into the sides. Both came in #738 bags.
So, basically, what's my play here? Do I have a bad strand or do I just need to take my stuff back to the drawing board? Please and thank you.

