I have a Roku Ultra connected to a Samsung UHDTV with HDMI. Occasionally while watching TV the screen will go black and audio will cut out, then after a few seconds it comes back on. I have changed HDMI cables and the HDMI port on the TV (moved cable from HDMI 2 to HDMI 1). The only way to get it to stop is to physically pull the power plug, wait a few seconds, then plug it back in. This will "fix" it for a few weeks to a month, then it comes back. It is definitely the Roku causing the issue. Let me tell you, this did not go over well during our Super Bowl party...
