So before I destroy all the matrix, could somebody tell me what's i'm doing wrong?
I did get some RGB LEDs from ebay and I found that about three of the batch of 50 burnt out with only a few mA going through them. I also found that the red was rather dim on all but one of the LEDs. I think that some LEDs you get on ebay are actually from the reject bin.
I'll retry with a 1K resistor and keep you informed but basically that's what I did with the 27K so I'm a bit confused.