I am trying to set up my ROKU express. The quick start guide (step 4) says I should use my TV remote to select the input I used to connect my streaming player. My xfinity provided remote is a very simple one and there is no obvious way to display my input options. 2 issues: (1) How do I do that and (2) I am concerned that, if I manage to display my input options, I may have a problem accessing my regular TV channels. I have a Samsung TV and all the setup instructions up to step 4 (select input) worked just fine.