I'm having trouble with videos on a freshly formatted (in the P4P) 128GByte card.

I can start filming, and it will run for a few minutes and then stop on its own - at which point I can re-start it.

When I examine the video later, the first file is just short of 4GBytes long, and unplayable.

This seems to happen regularly.  Has anybody else seen it and is there a common cause?

Just following up on this.  The problem appears to be related to the memory card.

When I used a SanDisk Ultra 128 GB MicroSDXC UHS-I card, I saw the problem on every flight.

I've switched to a Samsung Memory 64GB Evo MicroSDXC UHS-I Grade 1 Class 10 card, and this seems to work perfectly - no corruption at all.

So, it seems our P4Ps are quite picky about the cards we use.   I benchmarked the write performance of both cards and in fact, the larger card seems better, so it looks like there is something else going on.

Strange!

So..  looking into this further it appears that the 'U1' MicroSDXC cards support a guaranteed write speed of 10 MBytes/sec, which is lower than the 100Mbit/s (= approx 12.5 MBytes/sec) that the P4P can produce..
I am guessing that much of the time it is 'okay', but sometimes it can't keep up, leading to corruption.

I'll be ordering a U3 (30 MBytes/sec) card today...