Yay! This is now fixed in the master branch!
I finally found some time to dig into this bug, but before git bisect-ing, i tried building the master branch (commit 7932f3f3c7). Screen tearing is now gone!
My best guess is that it was fixed by this pull request: Rockchip: next update by knaerzche · Pull Request #5143 · LibreELEC/LibreELEC.tv · GitHub
I have the first model ASUS Tinker Board (non S version), and I'm experiencing the same symptoms. But strangely enough, all the 3840x2160 videos I tested from jell.yfish.us worked fine. Movies and Series all had tearing.
I tested the following versions:
LibreELEC-TinkerBoard.arm-9.2.6-rk3288.img.gz
LibreELEC-TinkerBoard.arm-9.1.502-rk3288.img.gz
LibreELEC-TinkerBoard.arm-9.1.501-rk3288.img.gz
Only 9.1.501 worked fine. I think you should switch the download page to point to that release.
Thanks for all the work that goes into creating LibreELEC!
These are the new commits in 9.1.502: Comparing 9.1.501...9.1.502 · LibreELEC/LibreELEC.tv · GitHub
Could this be the pull request that introduced the regression? Rockchip: update rkmpp and sync linux config by Kwiboo · Pull Request #3801 · LibreELEC/LibreELEC.tv · GitHub
Ping Kwiboo
