I build a K8021 control unit in 2009 and it has been working fine until now.
However yesterday when I switched it on it was set on the phone input and would not go to any other input when I pressed the buttons. I took the VK8021 IC out and put it back and it worker on other inputs for about 1 minute then went back to the phono input.
Can you help?
Regards Mike Harvey
Check if the problem is not power supply related. An intermittent power supply could cause a reset of the controller, which will make it jump to the default input selection.
If the controller should prove faulty, please return it for inspection/exchange.