Hi all - I have a brand new Roku Ultra and I can't cast videos from my Samsung S9 phone to the Roku using the Roku phone app. The videos are MP4 and default videos taken with the phone. I have never cast a video because the video loads partially and gets stuck while "retrieving" is on the screen. Then it says "Video Failed to Play." In the Roku app, I go to Media, Videos, and select a video to cast. I had a chat with customer support and I unplugged the Roku, plugged it back in and saw the bouncing Roku logo, and the result is still the same and the videos won't cast. I uninstalled and reinstalled the Roku phone app. Is this unusual for a brand new Roku Ultra?