When burning subtitles, I pick an .srt file which is supposed to be automatically converted to .ssa by avidemux. The resulting subtitles have multiple errors including missing lines, delays, display of consecutive lines at the same time etc...
I solved the problem by using a separate program that converts .srt to .ssa before adding it to avidemux, but I am just flagging this issue for your attention in case you want to fix it.
Thanks
It would help if you told/documented what those errors are. You can append .srt sample file to your posting
Now you leave the developer(s) in the dark.