Application: systemsettings (1.0)
KDE Platform Version: 4.4.1 (KDE 4.4.1) (Compiled from sources)
Qt Version: 4.6.2
Operating System: Linux 2.6.31-gentoo-r6 x86_64
Distribution (Platform): Gentoo Packages

-- Information about the crash:
Playing a test sound with xine, then quickly switching to gstreamer (test sound stops) and then hitting test sound again just crashed the Phonon control panel. 

 -- Backtrace:
Application: Systemeinstellungen (systemsettings), signal: Aborted
[Current thread is 1 (Thread 0x7f212e554740 (LWP 18487))]

Thread 3 (Thread 0x7f2112091910 (LWP 23295)):
#0  0x00007f212b22e189 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007f211cef63e3 in fifo_buffer_get () from /usr/lib64/libxine.so.1
#2  0x00007f211cefbb9f in video_decoder_loop () from /usr/lib64/libxine.so.1
#3  0x00007f212b22a297 in start_thread () from /lib/libpthread.so.0
#4  0x00007f212a7f68cd in clone () from /lib/libc.so.6
#5  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f2111890910 (LWP 23296)):
#0  0x00007f212b22e189 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007f211cef63e3 in fifo_buffer_get () from /usr/lib64/libxine.so.1
#2  0x00007f211cefcbdf in audio_decoder_loop () from /usr/lib64/libxine.so.1
#3  0x00007f212b22a297 in start_thread () from /lib/libpthread.so.0
#4  0x00007f212a7f68cd in clone () from /lib/libc.so.6
#5  0x0000000000000000 in ?? ()
The current source language is "auto; currently asm".

Thread 1 (Thread 0x7f212e554740 (LWP 18487)):
[KCrash Handler]
#5  0x00007f212a758315 in raise () from /lib/libc.so.6
#6  0x00007f212a759811 in abort () from /lib/libc.so.6
#7  0x00007f212b4b390d in qt_message_output(QtMsgType, char const*) () from /usr/lib64/qt4/libQtCore.so.4
#8  0x00007f212b4b3aad in qt_message(QtMsgType, char const*, __va_list_tag*) () from /usr/lib64/qt4/libQtCore.so.4
#9  0x00007f212b4b3c45 in qFatal(char const*, ...) () from /usr/lib64/qt4/libQtCore.so.4
#10 0x00007f21172b1c98 in Phonon::Gstreamer::MediaNode::disconnectNode(QObject*) () from /usr/lib64/kde4/plugins/phonon_backend/phonon_gstreamer.so
#11 0x00007f211e40ed21 in Phonon::PathPrivate::executeTransaction(QList<QPair<QObject*, QObject*> > const&, QList<QPair<QObject*, QObject*> > const&) () from /usr/lib64/libphonon.so.4
#12 0x00007f211e410bc7 in Phonon::PathPrivate::phononObjectDestroyed(Phonon::MediaNodePrivate*) () from /usr/lib64/libphonon.so.4
#13 0x00007f211e40dca6 in Phonon::MediaNodePrivate::~MediaNodePrivate() () from /usr/lib64/libphonon.so.4
#14 0x00007f211e40d315 in Phonon::MediaObjectPrivate::~MediaObjectPrivate() () from /usr/lib64/libphonon.so.4
#15 0x00007f211e40aecb in Phonon::MediaObject::~MediaObject() () from /usr/lib64/libphonon.so.4
#16 0x00007f211d87bff3 in DevicePreference::on_testPlaybackButton_toggled(bool) () from /usr/lib64/kde4/kcm_phonon.so
#17 0x00007f211d881b6f in DevicePreference::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib64/kde4/kcm_phonon.so
#18 0x00007f212b5c0a47 in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib64/qt4/libQtCore.so.4
#19 0x00007f212c804112 in QAbstractButton::toggled(bool) () from /usr/lib64/qt4/libQtGui.so.4
#20 0x00007f212c525fd1 in QAbstractButton::setChecked(bool) () from /usr/lib64/qt4/libQtGui.so.4
#21 0x00007f212c525c6a in QAbstractButtonPrivate::click() () from /usr/lib64/qt4/libQtGui.so.4
#22 0x00007f212c525f2c in QAbstractButton::mouseReleaseEvent(QMouseEvent*) () from /usr/lib64/qt4/libQtGui.so.4
#23 0x00007f212c5f045a in QToolButton::mouseReleaseEvent(QMouseEvent*) () from /usr/lib64/qt4/libQtGui.so.4
#24 0x00007f212c1e57c2 in QWidget::event(QEvent*) () from /usr/lib64/qt4/libQtGui.so.4
#25 0x00007f212c18edcd in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib64/qt4/libQtGui.so.4
#26 0x00007f212c196d2c in QApplication::notify(QObject*, QEvent*) () from /usr/lib64/qt4/libQtGui.so.4
#27 0x00007f212d0c5b5b in KApplication::notify(QObject*, QEvent*) () from /usr/lib64/libkdeui.so.5
#28 0x00007f212b5ad973 in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib64/qt4/libQtCore.so.4
#29 0x00007f212c1958cb in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) () from /usr/lib64/qt4/libQtGui.so.4
#30 0x00007f212c216c18 in QETWidget::translateMouseEvent(_XEvent const*) () from /usr/lib64/qt4/libQtGui.so.4
#31 0x00007f212c215dcc in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib64/qt4/libQtGui.so.4
#32 0x00007f212c23dfaa in x11EventSourceDispatch(_GSource*, int (*)(void*), void*) () from /usr/lib64/qt4/libQtGui.so.4
#33 0x00007f2127700e61 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#34 0x00007f21277043f8 in g_main_context_iterate () from /usr/lib/libglib-2.0.so.0
#35 0x00007f21277045ac in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#36 0x00007f212b5d6a8c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/qt4/libQtCore.so.4
#37 0x00007f212c23db4f in QGuiEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/qt4/libQtGui.so.4
#38 0x00007f212b5ac2e2 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/qt4/libQtCore.so.4
#39 0x00007f212b5ac6b4 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/qt4/libQtCore.so.4
#40 0x00007f212b5aeaa6 in QCoreApplication::exec() () from /usr/lib64/qt4/libQtCore.so.4
#41 0x0000000000411a7a in main ()

Reported using DrKonqi