I installed Debian Buster with Qt 5.11.3 with Mixxx 2.2.0 and there is the same problem, the waveform is scrolling smother if Mixxx is not in focus. I compile also the pull request https://github.com/mixxxdj/mixxx/pull/1974 but there is the same effect.
I remove the system Qt developer tools (headers etc) and try to compile Qt 5.12.1 again. Before compile Mixxx I set the PKG_CONFIG_PATH to /mnt/home/qt/lib/pkgconfig and now Mixxx found the new Qt library. But now Mixxx show another error on configure:
Configuring Qt
Checking for Qt5Core (5.0 or higher)... yes
Checking for C library Qt5X11Extras... no
ERROR:root:Unmet dependency: Could not find Qt5X11Extras or its development headers
I installed Debian Buster with Qt 5.11.3 with Mixxx 2.2.0 and there is the same problem, the waveform is scrolling smother if Mixxx is not in focus. I compile also the pull request https:/ /github. com/mixxxdj/ mixxx/pull/ 1974 but there is the same effect.
I remove the system Qt developer tools (headers etc) and try to compile Qt 5.12.1 again. Before compile Mixxx I set the PKG_CONFIG_PATH to /mnt/home/ qt/lib/ pkgconfig and now Mixxx found the new Qt library. But now Mixxx show another error on configure:
Configuring Qt
Checking for Qt5Core (5.0 or higher)... yes
Checking for C library Qt5X11Extras... no
ERROR:root:Unmet dependency: Could not find Qt5X11Extras or its development headers
How I compile Qt5X11Extras?