video blinking during session, long lag in accessing video appt on client side

Hi - I'm wondering if anyone else's video blinks out for a second during video calls. This has been happening for the last several months for me. I come right back, but it is distracting. I have a few clients who report needing several minutes to login because it takes a very long time for them to connect to the session. I've prompted them to delete cookies/cache. Is anyone else having these issues?