Chromecast Frustrations

Dear Fitness Blender, I have a Vizio M55-E0 TV Cast Version 1.40.169511 Chromium Version SX7A-3.0.361.8. I’m trying to cast Fitness Blender Plus videos to the TV from a windows laptop using chrome browser, no luck. Also tried casting from Android phone, no luck. Both devices begin to cast but the video starts, then pauses, over and over then errors out (returns to chrome cast home screen). From the laptop, I can choose to link to the Youtube video, but then Youtube adds advertisements. TV is hard wired to network (Ethernet) phone and laptop wireless to same network. Using the Ads free player on Blender account setting. Side note, screen mirroring from phone works, just not how I want to use it on a daily basis. Seems like this should just work but it doesn’t. Any advice is appreciated.