I have been seeing intermittent dropped video frames, usually around 30 at a time, in 4K recorded video. I was using one of the 64 GB SanDisk Extreme U3/V30 cards that is both on the DJI approved list and has earned good reports on the forum so initially I assumed that it wasn't the problem, but after being unable to find any other cause I compared to the 16 GB Panasonic card that came with the P4P and lo and behold, no problem when using the Panasonic card. I then had the SanDisk card replaced under warranty with an identical unit and so far I have been completely unable to duplicate the problem, so it appears that I did have a defective SD card even though it was new. The card wasn't counterfeit since SanDisk approved the s/n and warranty RMA so it looks like I simply got a bad card, unlikely but it does happen. Something to think about if you are having intermittent video glitches... check your card against another known good unit even if you are 'sure' it is OK.