Eprgic, when you are driving LEDs in mux mode, no doubt that you are driving 1 LED at one time, but to achieve a resonable brightness, you have to give it a much more powerfull current. For example, to drive a 3mA led to the same brightness, you have to either give it 3mA of constant current OR in 1/8 mux mode, you have to give it approx 24mA for 1/8 the time (duty cycle). The experts also say that pulsing hig current reduces light emission efficiency so you will have to give more than 24mA in pulses.