You're talking to one of them. Disappointing failures of both mouse and keyboard resulting in returning hundreds of pounds worth of supposedly high-end products within months of purchase. At least one of the problems I had was also getting reported by others by the time I sent that product back, so it also looks like a design flaw and not just bad luck. I think you also need to install their resource-hungry, crash-prone software to make use of most of the special features too, though that's hardly relevant if keys are falling off and buttons aren't registering presses anyway.

I wouldn't even consider buying more peripherals from Corsair for a while. The quality isn't there and they don't work properly in a you-had-one-job kind of way. Worst of a bad bunch in my experience.