The #hyperdeck is a bit picky, but looks like the #h264 level is the main issue, set it to "main" then it happily plays videos. And obviously the video resolution and fps needs to match with the current settings.
If you're excited about the new @Blackmagic_News products announced today, and want to support me as well as a small business, I'm collecting affiliate links for preorder pages at @DVEStore on my website here! https://aaronpk.tv/blackmagic/
Blackmagic Design
Blackmagic Design creates the world’s highest quality products for the feature film, post and broadcast industries including URSA cameras, DaVinci Resolve and ATEM switchers.