I have the same issue that started recently on my 1900Pro using the Beta 7 firmware. Netflix will only play one title then error. It happens on different version of the netflix app also.
I did a factory reset last night and the issue still happens. Unless it's something new to the netflix app itself I can't think of what else might be doing it. I have tried netflix 6.2 and 6.19 from AptoidTV. The 4.7 at the top of the list will not install - I get an error saying package is corrupt.