I have had problem since I purchased a TCL Roku TV one week ago. I got in contact with TCL chat support where we spent 40 minutes and exhausted all options/ suggestions with chat support. I then called TCL support, we were on the phone for over two hours trying methods that I would never have thought of (i.e. secret menu). I used four laptops running windows 10 and one Mac with no results. All HDMI ports indicated, "no signal". I tried another laptop running windows 7 and it worked! In all three HDMI ports. It was then suggested that I try hooking up my laptops to my older TV, a Sharp Aquos. I found that connecting my laptops to the older TV worked as well. TCL customer support let me know that they would escalate my issue to their engineers and that would call me back within 72 hours. it has now been 7 days without a response. My last option is to bring it back to the store (Best Buy) that I purchased it and request an exchange to see if this issue clears itself up in a new, same model, TCL Roku TV.