My second modem does not work. It is the selected tv input by only shows a blank screen. I have restarted several times but still a black screen? How do I fix?
I merged your two (cross) posts. you said modem but do you actually mean a set top box? do you have a model number? is there a clock on the front of the set top box? is the HDMI connected to the HDMI marked 'out to TV'? what is the TV's HDMI input port name (usually marked on the plastic near the port)?