Hello hcsitas,
Thanks for posting to the Apple Support Communities, and I understand that Screen Mirroring doesn't consistently stay connected. I'll do what I can to help.
Here are some suggestions based on what you've done already:
- Check your TV's settings for anything that might prevent connections when content is paused or stops sending instructions. If it is a monitor, also check any sleep settings.
- Restart both the router and the iPhone then try opening a new video: Restart your iPhone
Try the rest of the suggestions in this link under "If your content gets interrupted or your network lags": If AirPlay or screen mirroring isn’t working on your device
Thanks and have a wonderful day.