Choppy youtube playback

I am having a problem with choppy playback when uploaded to youtube. I use the 320 X 240 frame rate. I have tried other frame rates as well, but the choppy playback continues. Any suggestions?

Which movie option have you used to export? Have you tried by exporting locally to see if it is still choppy by exporting it to same resolution? If not, check the keyframe in movie option by adding more.