Version:            (using KDE 4.2.0)
OS:                Linux
Installed from:    Ubuntu Packages

As in the short description. Have debugged with GDB and got this output and backtrace, pointing towards Phonon.

(gdb) run
Starting program: /usr/bin/kate --nocrashhandler
[Thread debugging using libthread_db enabled]
[New Thread 0xb5c26700 (LWP 22704)]
QFSFileEngine::open: No file name specified
[New Thread 0xb3beeb90 (LWP 22720)]
QPainter::begin: Cannot paint on a null pixmap
QPainter::end: Painter not active, aborted
QPainter::begin: Cannot paint on a null pixmap
QPainter::end: Painter not active, aborted
QPainter::begin: Cannot paint on a null pixmap
QPainter::end: Painter not active, aborted
QPainter::begin: Cannot paint on a null pixmap
QPainter::end: Painter not active, aborted
QPainter::begin: Cannot paint on a null pixmap
QPainter::end: Painter not active, aborted
[New Thread 0xae601b90 (LWP 22825)]
[New Thread 0xadc5fb90 (LWP 22827)]
[Thread 0xae601b90 (LWP 22825) exited]
kate(22704) Phonon::KdePlatformPlugin::createBackend: using backend:  "GStreamer"
[New Thread 0xae601b90 (LWP 22828)]
[Thread 0xae601b90 (LWP 22828) exited]
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) "NVidia CK804 with ALC850" 
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) ("x-phonon:CARD=0,DEV=0", "plughw:CARD=0,DEV=0") 
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) setProperty(device, "x-phonon:CARD=0,DEV=0" ) failed 
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) setProperty(device, "plughw:CARD=0,DEV=0" ) failed 
[New Thread 0xae601b90 (LWP 22829)]
[Thread 0xae601b90 (LWP 22829) exited]
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) "NVidia CK804 with ALC850" 
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) ("x-phonon:CARD=0,DEV=0", "plughw:CARD=0,DEV=0") 
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) setProperty(device, "x-phonon:CARD=0,DEV=0" ) failed 
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) setProperty(device, "plughw:CARD=0,DEV=0" ) failed 
[New Thread 0xae601b90 (LWP 22830)]
[Thread 0xae601b90 (LWP 22830) exited]
virtual bool Phonon::Gstreamer::AudioOutput::setOutputDevice(const Phonon::AudioOutputDevice&) "default" 

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xb5c26700 (LWP 22704)]
0xb6bd09d7 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
(gdb) bt
#0  0xb6bd09d7 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#1  0xb3c29fd3 in Phonon::AudioOutputAdaptor::outputDeviceIndexChanged (this=0x0, _t1=0) at /build/buildd/phonon-4.3.0/obj-i486-linux-gnu/phonon/moc_audiooutputadaptor_p.cpp:185
#2  0xb3c13216 in Phonon::AudioOutputPrivate::handleAutomaticDeviceChange (this=0xb06bda8, device2=@0xbf99d234, type=Phonon::AudioOutputPrivate::FallbackChange)
    at /build/buildd/phonon-4.3.0/phonon/audiooutput.cpp:366
#3  0xb3c144aa in Phonon::AudioOutputPrivate::setupBackendObject (this=0xb06bda8) at /build/buildd/phonon-4.3.0/phonon/audiooutput.cpp:269
#4  0xb3c12b85 in Phonon::AudioOutputPrivate::init (this=0xb06bda8, c=Phonon::NoCategory) at /build/buildd/phonon-4.3.0/phonon/audiooutput.cpp:85
#5  0xafa4cae5 in ?? () from /usr/lib/kde4/kfileaudiopreview.so
#6  0xafa4d5ef in KPluginFactory::createInstance<KFileAudioPreview, QWidget> () from /usr/lib/kde4/kfileaudiopreview.so
#7  0xb6ee1edf in KPluginFactory::create () from /usr/lib/libkdecore.so.5
#8  0xb7efcc60 in KFileMetaPreview::createAudioPreview () from /usr/lib/libkio.so.5
#9  0xb7efcf74 in KFileMetaPreview::previewProviderFor () from /usr/lib/libkio.so.5
#10 0xb7efca9c in KFileMetaPreview::showPreview () from /usr/lib/libkio.so.5
#11 0xb5e97d12 in KDirOperator::Private::_k_showPreview () from /usr/lib/libkfile.so.4
#12 0xb5e983cd in KDirOperator::Private::_k_triggerPreview () from /usr/lib/libkfile.so.4
#13 0xb5ea49aa in KDirOperator::qt_metacall () from /usr/lib/libkfile.so.4
#14 0xb6bcfc40 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#15 0xb6bd09c2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#16 0xb752e623 in QAbstractItemView::entered () from /usr/lib/libQtGui.so.4
#17 0xb7539b4b in QAbstractItemView::mouseMoveEvent () from /usr/lib/libQtGui.so.4
#18 0xb7551972 in QListView::mouseMoveEvent () from /usr/lib/libQtGui.so.4
#19 0xb70c478b in QWidget::event () from /usr/lib/libQtGui.so.4
#20 0xb73fc083 in QFrame::event () from /usr/lib/libQtGui.so.4
#21 0xb749284f in QAbstractScrollArea::viewportEvent () from /usr/lib/libQtGui.so.4
#22 0xb753dd3f in QAbstractItemView::viewportEvent () from /usr/lib/libQtGui.so.4
#23 0xb7494df5 in ?? () from /usr/lib/libQtGui.so.4
#24 0xb6bba20a in QCoreApplicationPrivate::sendThroughObjectEventFilters () from /usr/lib/libQtCore.so.4
#25 0xb706c82a in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#26 0xb7075081 in QApplication::notify () from /usr/lib/libQtGui.so.4
#27 0xb7b8607d in KApplication::notify () from /usr/lib/libkdeui.so.5
#28 0xb6bbb021 in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#29 0xb707430e in QApplicationPrivate::sendMouseEvent () from /usr/lib/libQtGui.so.4
#30 0xb70de646 in ?? () from /usr/lib/libQtGui.so.4
#31 0xb70dd9d5 in QApplication::x11ProcessEvent () from /usr/lib/libQtGui.so.4
#32 0xb710779a in ?? () from /usr/lib/libQtGui.so.4
#33 0xb6027c38 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#34 0xb602b2e3 in ?? () from /usr/lib/libglib-2.0.so.0
#35 0xb602b4a1 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#36 0xb6be5658 in QEventDispatcherGlib::processEvents () from /usr/lib/libQtCore.so.4
#37 0xb7106e95 in ?? () from /usr/lib/libQtGui.so.4
#38 0xb6bb96ea in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#39 0xb6bb98aa in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#40 0xb74d99d7 in QDialog::exec () from /usr/lib/libQtGui.so.4
#41 0xb7ef1756 in KEncodingFileDialog::getOpenUrlsAndEncoding () from /usr/lib/libkio.so.5
#42 0xb8026cc2 in KateViewManager::slotDocumentOpen (this=0xa15dc08) at /build/buildd/kdesdk-4.2.0/kate/app/kateviewmanager.cpp:178
#43 0xb8027300 in KateViewManager::qt_metacall (this=0xa15dc08, _c=QMetaObject::InvokeMetaMethod, _id=8, _a=0xbf99ea6c)
    at /build/buildd/kdesdk-4.2.0/obj-i486-linux-gnu/kate/app/kateviewmanager.moc:122
#44 0xb6bcfc40 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#45 0xb6bd0040 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#46 0xb7066581 in QAction::triggered () from /usr/lib/libQtGui.so.4
#47 0xb7066eef in QAction::activate () from /usr/lib/libQtGui.so.4
#48 0xb748c682 in QToolButton::nextCheckState () from /usr/lib/libQtGui.so.4
#49 0xb73afda3 in ?? () from /usr/lib/libQtGui.so.4
#50 0xb73b0076 in QAbstractButton::mouseReleaseEvent () from /usr/lib/libQtGui.so.4
#51 0xb748cb7c in QToolButton::mouseReleaseEvent () from /usr/lib/libQtGui.so.4
#52 0xb70c4922 in QWidget::event () from /usr/lib/libQtGui.so.4
#53 0xb73ae0ae in QAbstractButton::event () from /usr/lib/libQtGui.so.4
#54 0xb748c644 in QToolButton::event () from /usr/lib/libQtGui.so.4
#55 0xb706c84c in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#56 0xb7075081 in QApplication::notify () from /usr/lib/libQtGui.so.4
#57 0xb7b8607d in KApplication::notify () from /usr/lib/libkdeui.so.5
#58 0xb6bbb021 in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#59 0xb707430e in QApplicationPrivate::sendMouseEvent () from /usr/lib/libQtGui.so.4
---Type <return> to continue, or q <return> to quit---
#60 0xb70de646 in ?? () from /usr/lib/libQtGui.so.4
#61 0xb70dd9d5 in QApplication::x11ProcessEvent () from /usr/lib/libQtGui.so.4
#62 0xb710779a in ?? () from /usr/lib/libQtGui.so.4
#63 0xb6027c38 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#64 0xb602b2e3 in ?? () from /usr/lib/libglib-2.0.so.0
#65 0xb602b4a1 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#66 0xb6be5658 in QEventDispatcherGlib::processEvents () from /usr/lib/libQtCore.so.4
#67 0xb7106e95 in ?? () from /usr/lib/libQtGui.so.4
#68 0xb6bb96ea in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#69 0xb6bb98aa in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#70 0xb6bbbf65 in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#71 0xb706c6c7 in QApplication::exec () from /usr/lib/libQtGui.so.4
#72 0xb806073d in kdemain (argc=2, argv=0xbf99ffc4) at /build/buildd/kdesdk-4.2.0/kate/app/katemain.cpp:250
#73 0x08048672 in main (argc=Cannot access memory at address 0x8
) at /build/buildd/kdesdk-4.2.0/obj-i486-linux-gnu/kate/app/kate_dummy.cpp:3