Unplug all HDMI connections from the set then power off and UNPLUG the power from the set.
Why? HDMI chips employ HDCP (you can google that, I will not duplicate the web on that.) And part of that system can have ports stop working with devices until they reset. To hurry this along we use this old TV tech trick in my first sentence.
Wait 10 minutes then apply power and hook it up the way you want.
As to HDMI cables, CNET and other sites have plenty to say. I'll share I use the AmazonBasics and they are great.
I've had this problem for a while now, but I now thought I better ask here so that I may find a solution. My TV is regular off-brand 1080p LCD that my parents got back in 2012's summer. It was the same summer I got my Xbox 360, and when we got the TV, I bought a regular HDMI cable and connected it to HDMI port 1. it had first worked properly for maybe 2 months or so, but then I found that it's not working and instead I switched the cable to port 2. Until then there was no problem, and after a while I noticed that my parents used their HD receiver on HDMI port 1, so I thought it had worked again. Then my brother bought me a PS4 and I got it last Jan. For the time being, I had used the same old HDMI cable that is still connected to HDMI port 2, and I just switched it between PS4 and the Xbox and everything was working fine.... that is until my brother got me a supposedly high-quality HDMI cable by the brand name of 4g made specifically for the PS4, because i wanted to connect both and just switch the source from my remote control whenever I like. So then I connected it to HDMI1, and the TV displayed video without audio. I then connected it to HDMI2 in place of the old cable; at first, it worked, but then, when I switched the source or maybe turned off the PS4 (I don't clearly remember), it now also showed only video. I kept switching the cables and so, and then the weird thing, the old cable, connected to the Xbox 360 and HDMI port 2, now had the same problem...... it was like an infection that began from HDMI port 1, infected the new cable, then the new cable infected port 2, and port 2 infected the old cable...... If I turn the console before the TV, it shows a black screen, and only video with no sound when vice versa; and now the TV shows the display info "1980x1080@60Hz" instead of "1080p@60Hz" (which I know is supposedly the same but just messed up). That all was before my summer vacation, and I left them like that, not knowing what or where exactly now is the problem, and afraid it was irreversible, or that it affected the consoles; and when I got my vacation, I found a solution for the Xbox: I turned off the automatic display discovery that I had left on ever since I got the Xbox, and set the display to 1080p, which I found better for me because I now forced the display of all the games into 1080p. But then for the PS4 the same solution didn't work, but what I kept doing the whole summer every time I wanted to play is that I turn it on, remove the HDMI cable (the old one which is connected to HDMI2) from it and put the other, new one in its place (which, I forgot to mention, is, ironically, now never works with the PS4 -even with this method- and I use it for the xbox), then switch the source to HDMI1 which shows the black screen (it works without problems with the xbox now), then return the old cable in the PS4, and then switch the source back to HDMI2 and it displays 1080p@60Hz, which is, as I mentioned, my indicator that there is sound now. My hunch is that it's a firmware problem in the TV. So anyway the question is: is it fixable by any means? since it's seemingly a long time until I get a new TV, and now it's the best one for me. Forgive my recitation of many details but it's a confusing problem, and thanks.