We got our ROku Soundbar on Wednesday, set it up with little to no problems. Its only HDMI so the optical cable had to be used as well. Worked well, even with the turning the TV on and off. We enjoyed watching shows Thursday and Friday night. Today (Saturday), we went to turn it on, TV came on, and we got "Unknown Signal" on the TV. You can hear the beeps of the Soundbar when you press buttons on the remote... so I assumed there was power and everything with the sound bar. I plugged my laptop into the HDMI Port and it worked just fine. When I unplugged the soundbar and plugged it back in .. the TV Did display the little bouncing ROKU screen, then... "Unknown signal". I cant get to the settings of the soundbar as I cant get the screen.... so is there any suggestions on what else I can try??
I only have one HDMI port on the TV. I tried two different cables and even plugged my computer into the HDMI port of the TV in order to see if it was the TV. The TV displayed the computer screen just fine.
I did however, do a factory reset (pushing the reset button for 10 seconds) and it started with the setup screen again. It has been working since with one important modification. I didn't change the display from 720p to Automatic (or 1080p). I have a feeling that we only watched things in 720p prior to it failing. When we attempted to watch something in 1080p.. the Roku automatically switched the signal.. and the TV freaked... and there was nothing to reset the soundbar back to 720p. Once I went through the setup again, I set it to only do 720p.. and we haven't had a problem since.
So the solution in this case:
Set specifically to a lower resolution that will work on the TV