Random SPI Signals on LPD8806 LED Strip
Here is my interpretation of what I think is happening: -

The chips used in this product require clocked serial data and each chip has outputs that can feed more chips thus, you can create a large array of LEDs and each LED can be controlled individually. That seems to be the idea but, the general problem with controlling LEDs through an array of shift registers is that the guy writing the code to control the LEDs has to keep tabs on what the state of the LEDs are. 

No easy feat and say, because of the size of the array a rogue clock occured, the "controller" (aka MCU) wouldn't necessarily be aware that the "system" is now out of sync. I'm half assuming that the chips are distributed through the product so that LED wiring is made simpler - this can aggrevate the problem if there is interference from some external source - I can envisage random LEDs turning on and maybe this is the problem.

The chip does not appear to be 100% adequately documented and of course there is no guarantee that adequate supply decoupling is used in the produce purchased so it's a bit of a lottery as to what is really happening but, given the "antenna"-like nature of the product and also the lack of adequate grounding throughout the strip of LEDs, external influences could have an effect.



Maybe the problem comes from a local wifi router or someone using a drill nearby; maybe someone using an electric arc welder or maybe just a faulty product.