Hi there, rkfromepping!
Thanks for reaching out to the Apple Support Communities! It sounds like you are having an issue with poor video connection on FaceTime and I am happy to help out! I recommend taking a look at this article with steps to follow If you can't make a FaceTime call on your iPhone, iPad, or iPod touch. Specifically:
If your cellular connection or Wi-Fi network are running slow, or other users are streaming audio or video on the same Wi-Fi network, you might have these issues:
- Connection alerts or unable to connect
- Choppy video calls
- Black screen
- Dropped calls
Make sure that both you and the person that you're calling are using a fast Wi-Fi or cellular connection. If you’re using Wi-Fi, FaceTime requires a broadband connection.
I also suggest testing the calls on a different Wi-Fi network as well as on cellular data to see if there is a difference.
Let me know the results and if you have noticed the issue with any other contacts or only with the one specific contact.