Animated gifs colours off but for first and last frames

Hi,

I'm resurrecting a thread that was not resolved but I'm experiencing the same problem.

I have managed to export short videos to animated gifs in the past but for some reason I can't get it to work today.

I'm sending a 1080p h264 FCPX project to Compressor where I apply an Animated Image preset to output gif, max 1080p at 10fps. The colour preset is the default Floyd-steinberg global 256 colours dithering.

The first and last frames come out ok

In-between the colours are completely off.

Here are the Compressor settings:

I'm surprised because there aren't that many colours on this image.

I tried the Sierra 2 dithering and the result is almost the same.

Is this because the dithering algorithms are optimised for nature and not screen recordings?

Is this a bug?

Would you recommend another software than Compressor?