I've heard that the Noppoo in particular has chattering issue, more so than other boards.
Well that would prove to be true on my end, I've not even had it 9 months before the chattering started and to be honest, I really like the Noppoo it's perfect for me, especially with the switches that I'm using (reds), I'd just like to be able to fix it so that I can sell off my Keycool, but I'm not sure if that's even possible.
*crosses fingers*
edit: I have no idea of what even caused mine, can something like this just be caused out of the blue, without any kind of trigger? or does something have to happen to the keyboard, I guess it would be general wear and tear though, iuno.