I am trying build Polyphone 1.7 on Ubuntu 18.04. I installed all the required dependencies and I am able to build Polyphone. If I build with Qt4 (qmake -qt4), the application refuses to start, throwing an invalid pointer exception. If I build with Qt5, the application starts just fine but if I try to open a soundfont, the application hangs. The very same Polyphone version works just fine on Ubuntu 16.04. I tried compilling the app in DEBUG mode (qmake CONFIG+=debug) to try and see what happens but instead of the usual hang or crash on start up, the application works just fine, I am able to open up a soundfont, inspect it, play the presets and so on. The problem is though that it is really slow so it is unusable. Any ideas how to troubleshoot this? I can provide additional info, just tell me what you need.
