I have 10.5.0 build 4201-AE.
The menus work fine, I can select channels, select shows/movies, but as soon as I start to stream anything, the screen goes blank. Audio works fine.
I tried Netflix, ROKU channel, Fox sports, Showtime Anytime...
I know there have been issues reported with other models, but I don't see any other reports for the 3930x Roku Express.
Anyone else seeing this?