1. Click tray icon
2. Open mixer from popup
3. Go into config dialog
4. Change slider orientations to horizontal
5. Click Apply
6. Kaboom

-- Backtrace:
Application: KMix (kmix), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f320a876800 (LWP 2201))]

Thread 2 (Thread 0x7f3201894700 (LWP 2202)):
#0  0x00007f32166cb1dd in poll () from /lib64/libc.so.6
#1  0x00007f3214024142 in _xcb_conn_wait () from /lib64/libxcb.so.1
#2  0x00007f3214025ccf in xcb_wait_for_event () from /lib64/libxcb.so.1
#3  0x00007f320422ebd7 in QXcbEventReader::run (this=0x8a6b60) at qxcbconnection.cpp:1089
#4  0x00007f3217cee885 in QThreadPrivate::start (arg=0x8a6b60) at thread/qthread_unix.cpp:337
#5  0x00007f32147c052a in start_thread () from /lib64/libpthread.so.0
#6  0x00007f32166d677d in clone () from /lib64/libc.so.6

Thread 1 (Thread 0x7f320a876800 (LWP 2201)):
[KCrash Handler]
#6  0x00007f3218a29a70 in QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::data (this=0x8) at ../../include/QtCore/../../src/corelib/tools/qscopedpointer.h:135
#7  0x00007f3218a282f6 in qGetPtrHelper<QScopedPointer<QObjectData> > (p=...) at ../../include/QtCore/../../src/corelib/global/qglobal.h:961
#8  0x00007f3218a28bda in QAction::d_func (this=0x0) at kernel/qaction.h:56
#9  0x00007f3218a26ed1 in QAction::setEnabled (this=0x0, b=true) at kernel/qaction.cpp:1025
#10 0x00007f321dd7fdf9 in KMixDockWidget::controlsChange (this=0xb402c0, changeType=8) at /home/sho/devel/src/kde/kdemultimedia/kmix/gui/kmixdockwidget.cpp:109
#11 0x00007f321ddb7f7e in KMixDockWidget::qt_static_metacall (_o=0xb402c0, _c=QMetaObject::InvokeMetaMethod, _id=3, _a=0x7fff77a61060) at /home/sho/devel/build/kde/kdemultimedia/kmix/moc_kmixdockwidget.cpp:96
#12 0x00007f3217f1b5f1 in QMetaMethod::invoke (this=0x7fff77a61520, object=0xb402c0, connectionType=Qt::DirectConnection, returnValue=..., val0=..., val1=..., val2=..., val3=..., val4=..., val5=..., val6=..., val7=..., val8=..., val9=...) at kernel/qmetaobject.cpp:2183
#13 0x00007f3217f1aac5 in QMetaObject::invokeMethod (obj=0xb402c0, member=0x7f321ddc9c58 "controlsChange", type=Qt::DirectConnection, ret=..., val0=..., val1=..., val2=..., val3=..., val4=..., val5=..., val6=..., val7=..., val8=..., val9=...) at kernel/qmetaobject.cpp:1478
#14 0x00007f321dd5b4ab in QMetaObject::invokeMethod (obj=0xb402c0, member=0x7f321ddc9c58 "controlsChange", type=Qt::DirectConnection, val0=..., val1=..., val2=..., val3=..., val4=..., val5=..., val6=..., val7=..., val8=..., val9=...) at /home/sho/devel/src/qt5/qtbase/src/corelib/kernel/qobjectdefs.h:391
#15 0x00007f321dda8aaf in ControlManager::announce (this=0x7f321dff8ef0 <ControlManager::instanceSingleton>, mixerId=..., changeType=ControlChangeType::MasterChanged, sourceId=...) at /home/sho/devel/src/kde/kdemultimedia/kmix/core/ControlManager.cpp:79
#16 0x00007f321dd83b14 in KMixPrefDlg::updateSettings (this=0xa2dba0) at /home/sho/devel/src/kde/kdemultimedia/kmix/gui/kmixprefdlg.cpp:336
#17 0x00007f321b1b935a in KConfigDialog::qt_static_metacall (_o=0xa2dba0, _c=QMetaObject::InvokeMetaMethod, _id=2, _a=0x7fff77a61c60) at /home/sho/devel/build/frameworks/kconfigwidgets/src/moc_kconfigdialog.cpp:120
#18 0x00007f3217f528df in QMetaObject::activate (sender=0xa66d90, signalOffset=7, local_signal_index=2, argv=0x7fff77a61c60) at kernel/qobject.cpp:3716
#19 0x00007f3217f520f0 in QMetaObject::activate (sender=0xa66d90, m=0x7f32190aeea0 <QAbstractButton::staticMetaObject>, local_signal_index=2, argv=0x7fff77a61c60) at kernel/qobject.cpp:3582
#20 0x00007f3218e8bed0 in QAbstractButton::clicked (this=0xa66d90, _t1=false) at .moc/moc_qabstractbutton.cpp:298
#21 0x00007f3218b58ffd in QAbstractButtonPrivate::emitClicked (this=0xa6b7b0) at widgets/qabstractbutton.cpp:534
#22 0x00007f3218b58f8c in QAbstractButtonPrivate::click (this=0xa6b7b0) at widgets/qabstractbutton.cpp:527
#23 0x00007f3218b5a46c in QAbstractButton::mouseReleaseEvent (this=0xa66d90, e=0x7fff77a62960) at widgets/qabstractbutton.cpp:1132
#24 0x00007f3218a87349 in QWidget::event (this=0xa66d90, event=0x7fff77a62960) at kernel/qwidget.cpp:8650
#25 0x00007f3218b5a2aa in QAbstractButton::event (this=0xa66d90, e=0x7fff77a62960) at widgets/qabstractbutton.cpp:1089
#26 0x00007f3218c11f64 in QPushButton::event (this=0xa66d90, e=0x7fff77a62960) at widgets/qpushbutton.cpp:673
#27 0x00007f3218a37ff0 in QApplicationPrivate::notify_helper (this=0x89b360, receiver=0xa66d90, e=0x7fff77a62960) at kernel/qapplication.cpp:3722
#28 0x00007f3218a35f75 in QApplication::notify (this=0x88a680, receiver=0xa66d90, e=0x7fff77a62960) at kernel/qapplication.cpp:3280
#29 0x00007f3217f0f47e in QCoreApplication::notifyInternal (this=0x88a680, receiver=0xa66d90, event=0x7fff77a62960) at kernel/qcoreapplication.cpp:932
#30 0x00007f3218a3ac2d in QCoreApplication::sendSpontaneousEvent (receiver=0xa66d90, event=0x7fff77a62960) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#31 0x00007f3218a3484b in QApplicationPrivate::sendMouseEvent (receiver=0xa66d90, event=0x7fff77a62960, alienWidget=0xa66d90, nativeWidget=0xa2dba0, buttonDown=0x7f32190b8a10 <qt_button_down>, lastMouseReceiver=..., spontaneous=true) at kernel/qapplication.cpp:2751
#32 0x00007f3218aaedad in QWidgetWindow::handleMouseEvent (this=0xc61970, event=0x7fff77a63460) at kernel/qwidgetwindow.cpp:499
#33 0x00007f3218aadbe9 in QWidgetWindow::event (this=0xc61970, event=0x7fff77a63460) at kernel/qwidgetwindow.cpp:171
#34 0x00007f3218a37ff0 in QApplicationPrivate::notify_helper (this=0x89b360, receiver=0xc61970, e=0x7fff77a63460) at kernel/qapplication.cpp:3722
#35 0x00007f3218a35760 in QApplication::notify (this=0x88a680, receiver=0xc61970, e=0x7fff77a63460) at kernel/qapplication.cpp:3164
#36 0x00007f3217f0f47e in QCoreApplication::notifyInternal (this=0x88a680, receiver=0xc61970, event=0x7fff77a63460) at kernel/qcoreapplication.cpp:932
#37 0x00007f32182ff0ab in QCoreApplication::sendSpontaneousEvent (receiver=0xc61970, event=0x7fff77a63460) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#38 0x00007f32182f8958 in QGuiApplicationPrivate::processMouseEvent (e=0xae1650) at kernel/qguiapplication.cpp:1795
#39 0x00007f32182f7f78 in QGuiApplicationPrivate::processWindowSystemEvent (e=0xae1650) at kernel/qguiapplication.cpp:1598
#40 0x00007f32182e1629 in QWindowSystemInterface::sendWindowSystemEvents (flags=...) at kernel/qwindowsysteminterface.cpp:564
#41 0x00007f320426f422 in userEventSourceDispatch (source=0x8e8a30) at eventdispatchers/qeventdispatcher_glib.cpp:70
#42 0x00007f321720aafb in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
#43 0x00007f321720ae98 in g_main_context_iterate.isra () from /lib64/libglib-2.0.so.0
#44 0x00007f321720af4c in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#45 0x00007f3217f8878b in QEventDispatcherGlib::processEvents (this=0x8dda50, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#46 0x00007f320426f644 in QPAEventDispatcherGlib::processEvents (this=0x8dda50, flags=...) at eventdispatchers/qeventdispatcher_glib.cpp:115
#47 0x00007f3217f0c122 in QEventLoop::processEvents (this=0x7fff77a63a20, flags=...) at kernel/qeventloop.cpp:128
#48 0x00007f3217f0c3fb in QEventLoop::exec (this=0x7fff77a63a20, flags=...) at kernel/qeventloop.cpp:204
#49 0x00007f3217f0fb58 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1185
#50 0x00007f32182f7d24 in QGuiApplication::exec () at kernel/qguiapplication.cpp:1532
#51 0x00007f3218a34f8d in QApplication::exec () at kernel/qapplication.cpp:2956
#52 0x00007f321dd716e8 in kdemain (argc=5, argv=0x7fff77a64028) at /home/sho/devel/src/kde/kdemultimedia/kmix/apps/main.cpp:91
#53 0x0000000000400be8 in main (argc=5, argv=0x7fff77a64028) at /home/sho/devel/build/kde/kdemultimedia/kmix/kmix_dummy.cpp:3


Reproducible: Always