Colibri imx6dl with analog camera adapter, jittery video

I get very jittery (wobbly?) video when capturing a composite NTSC signal from a Micca G2 Media Player

The jitteriness is worse on the menu screen, but I still see it when playing a video as well. When I plug into a composite TV, there is no jitter.

I capture this file using this command:
gst-launch-1.0 imxv4l2videosrc ! imxvpuenc_h264 ! mpegtsmux ! filesink location=jittery.h264.ts

Sample Jittery Video (MPEG/TS)

Is there anything I can do to fix this? I’ve tried changing framerates, deinterlace, but nothing has worked yet.