Since beta 2.2/qt5 (not in 2.1.4/qt4) the spinnys do not work proper under Ubuntu 18.04 (!!not under 16.04!!)
In my mixxx-development-environment i have two machines, one big box with Ubuntu mate 16.04 and a lenovo thinkpad edge 15 (TP) with ubuntu 18.04 bionic. The bug i mean only happens on the TP with bionic.
- Mostly the spinnys load a cover only, if a second deck has a track loaded. Curiously sometimes randomly a cover is loaded in the spinny.
- Then, when covers are loaded in both spinnys, they are spinning only if both decks are playing. if one deck stop playing - and it doesn't matter which one - both spinnys are stop spinning.
- When touching one Wheel for scratching, also both spinnys stop spinning.
When switching from big spinnys to normal, the behavior is the same.
In Ubuntu 16.04 i have not this behavior and i have there the same mixxx-releases with the same midi-mappings running. There are all spinnys work as well as they should, also the new big spinnys. So i think this is a bug in relation on ubuntu 18.04 bionic.
Are you compiling Mixxx yourself or are you using the packages from the PPA? What GPU (graphics card) are you using on each computer? If you use an nVidia GPU, are you using nVidia's proprietary driver?
If you're lucky, maybe this will be fixed by switching from QGLWidget to QOpenGLWidget (Bug #1687937).
Ubuntu 18.04 has Qt 5.9.5, which is a bit outdated. Perhaps there is an underlying bug in Qt which has been fixed since then?