During the maiden flight of our Inspire 1, we found the video would stop recording (at around 20 seconds) intermittantly. One or two files went for about a minute but no long duration shots.We used a SANDISC ULTRA HC I 32gb.
After scouring the web with no results the very next day an update was issued by DJI. So, using another SANDISC ULTRA 32gb card, I did the update and tested the video with success
Replaced the SD card with the original SD card and the problem returned. Looks like not all cards are the same after all. We also were on the highest frame and res.
More testing with the new card to be carried out....
Hope this helps someone