Got exactly the same problem with my i1 v2 ( it's a new machine) video signal constantly breaks up. Bars out or lags. Always when I'm am setting up a nice shot. Used to have a phantom 3. Worked perfectly always This is driving me mad. It's virtually I unuseable for photography. Tried...
There are no issues with lock down or the app or similar just do t upgrade the firmware unless you really really have to. If all is fine don't touch it ignore the prompts