RGB LED flickering

Other Hardware LEDs and Multiplexing
20

I got it!
I found this article: Arduino Playground - TimerPWMCheatsheet
I think it's a bit better explained here how you get to a solution.
So I just put this into setup:

void setup() {
   TCCR0A = _BV(COM0A1) | _BV(COM0B1) | _BV(WGM00);
   // other setup stuff
}

and made this change in the wiring.c file (revert this change! only use it for this one sketch so that the millis and delay are correct here):

// the prescaler is set so that timer0 ticks every 64 clock cycles, and the
// the overflow handler is called every 256 ticks.
#define MICROSECONDS_PER_TIMER0_OVERFLOW (clockCyclesToMicroseconds(64 * 510))