Sounds like a problem on your end :/
For the record, gfycat re-encodes video files to webm/vp8 and that’s where the quality hit happens. It doesn’t touch it if you directly upload it in that format. Well that’s how it’s supposed to work anyway.
edit: to clarify, mixtape is only an alternative; gfycat will always be my main link.
You can always pm me. That goes to everyone who sends me anon questions. Most of them end up unanswered cause they’re repetitive and I’m getting lazier cherry picking them.
Though most of my “technique” is good old fashioned trial and error, you can find a bit more info ctrl+f ing my answers page.