Source Monitor Not Playing on External Monitor

[Adobe2368]

Program monitor plays back fine. But when I click on the Source monitor, the picture freezes on wherever I have a play-head on my timeline. I currently have the monitor connected to my computer via the Ultrastudio Mini Monitor

[Michael Grenadier]

more than likely the video is a format that's not compatible with your output device...  Select the clip in the browser and hit command-9 to get the clip information....  and post back.  

[Adobe2368]

Maybe...H.264 640x360 .mp4 file. I figure the Ultrastudio could play back that?

[Michael Grenadier]

that's not a standard video frame size.   You might check the manual for the ultrastudio or post a question with blackmagic support...  If you make a sequence from the clip with clip settings does that sequence play out?