@Hippynerd: My LEDs (the cube itself) is defintely fine. I've tested it throughly before connecting it up to anything. The devil is hiding somewhere in the driver circuit. It seems to me that it's impossible for the software to be wrong as I'm only writing out 3 bytes to the 3 shift registers in the setup() function, loop() is completely empty, there's no sorcery in the software (yet 
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