09-23-2018 01:10 PM
Did you mean you are using the latest version of Quik for desktop application on your computer? Which version do you have? Make sure that you have the latest version which is 2.7.
How are you editing your content? Which camera model are you using? Do you recall which resolution settings you have used for your recordings?
Also, do the source video (before editing) play back good, that is, without quality issues? These details will help pus better understand the issue.
Hope to hear back from you.