I was recording mp4 files in h.264 directly from the camera, not AVCHD, unless of course I am missing something. The video files show h.264 compression.
I tried transcoding to ProRes, and I believe there was some improvement, but the files are still very choppy.
I also tried encoding the files in 720p, just to see, and they seemed to play fine. This makes me think that this is a hardware issue, but it’s very strange seeing as I never had trouble with 1080p mp4s from a GH3…anyone know if the system frequency control could have had an effect?