Found the issue
The gif had 25 frames, i removed a few frames in the middle (with ezgif) keeping only frames 1,5,10,15,20,25 and increased the delay between frames from 4ms - to 20 ms
is not clear movement but still works
It seems the glitch happens when a GIF has very small delay between frames, with 20ms delay seems to work fine
Thank you all for answering. I will keep trying to find the best setup to make it smoother