Application that crashed: k3b
Version of the application: 1.68.0
KDE Version: 4.3.3 (KDE 4.3.3)
Qt Version: 4.5.2
Operating System: Linux 2.6.31-14-generic i686
Distribution: Ubuntu 9.10

What I was doing when the application crashed:
not much to say..it just crashed. I ve seen reports of this behavior but the backtraces seem to be slightly different so I hope it might be of further help.

 -- Backtrace:
Application: K3b (k3b), signal: Segmentation fault
[Current thread is 1 (Thread 0xb7772920 (LWP 4378))]

Thread 4 (Thread 0xb5882b70 (LWP 4395)):
#0  0x004a0422 in __kernel_vsyscall ()
#1  0x0047c142 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0x0309b7e4 in pthread_cond_timedwait () from /lib/tls/i686/cmov/libc.so.6
#3  0x04b2c81e in ?? () from /usr/lib/libQtCore.so.4
#4  0x04b2c9c0 in QThread::sleep(unsigned long) () from /usr/lib/libQtCore.so.4
#5  0x006c72e9 in K3b::MediaCache::PollThread::run() () from /usr/lib/libk3b.so.6
#6  0x04b2ce32 in ?? () from /usr/lib/libQtCore.so.4
#7  0x0047780e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#8  0x0308e7ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 3 (Thread 0xb5081b70 (LWP 5837)):
[KCrash Handler]
#6  0x001cb00c in K3b::Msf::Msf(K3b::Msf const&) () from /usr/lib/libk3bdevice.so.6
#7  0x001c49be in K3b::Device::Track::firstSector() const () from /usr/lib/libk3bdevice.so.6
#8  0x006c4ea4 in K3b::Medium::analyseContent() () from /usr/lib/libk3b.so.6
#9  0x006c5bd0 in K3b::Medium::update() () from /usr/lib/libk3b.so.6
#10 0x006c725a in K3b::MediaCache::PollThread::run() () from /usr/lib/libk3b.so.6
#11 0x04b2ce32 in ?? () from /usr/lib/libQtCore.so.4
#12 0x0047780e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#13 0x0308e7ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 2 (Thread 0xb3efeb70 (LWP 5838)):
#0  0x004a0422 in __kernel_vsyscall ()
#1  0x0047be15 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0x0309b78d in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3  0x04b2c4d2 in ?? () from /usr/lib/libQtCore.so.4
#4  0x04b27ba2 in QMutex::lock() () from /usr/lib/libQtCore.so.4
#5  0x006c74c5 in K3b::MediaCache::resetDevice(K3b::Device::Device*) () from /usr/lib/libk3b.so.6
#6  0x006a75a4 in K3b::Device::DeviceHandler::run() () from /usr/lib/libk3b.so.6
#7  0x006935db in ?? () from /usr/lib/libk3b.so.6
#8  0x04b2ce32 in ?? () from /usr/lib/libQtCore.so.4
#9  0x0047780e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#10 0x0308e7ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb7772920 (LWP 4378)):
#0  0x00c197e0 in ?? () from /usr/lib/libkfile.so.4
#1  0x00bc7874 in ?? () from /usr/lib/libkfile.so.4
#2  0x00c211e0 in _fini () from /usr/lib/libkfile.so.4
#3  0x00dcbf46 in ?? () from /lib/ld-linux.so.2
#4  0x02ff105f in ?? () from /lib/tls/i686/cmov/libc.so.6
#5  0x02ff10cf in exit () from /lib/tls/i686/cmov/libc.so.6
#6  0x075cfd8b in ?? () from /usr/lib/libQtGui.so.4
#7  0x02893a9a in KApplication::xioErrhandler(_XDisplay*) () from /usr/lib/libkdeui.so.5
#8  0x02893ad6 in ?? () from /usr/lib/libkdeui.so.5
#9  0x004da2e6 in _XIOError () from /usr/lib/libX11.so.6
#10 0x004e1f8a in ?? () from /usr/lib/libX11.so.6
#11 0x004e28c6 in _XEventsQueued () from /usr/lib/libX11.so.6
#12 0x004cb5ff in XEventsQueued () from /usr/lib/libX11.so.6
#13 0x0760ddb5 in ?? () from /usr/lib/libQtGui.so.4
#14 0x03ba6cc1 in g_main_context_check () from /lib/libglib-2.0.so.0
#15 0x03ba746c in ?? () from /lib/libglib-2.0.so.0
#16 0x03ba7853 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#17 0x04c4802c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#18 0x0760dbe5 in ?? () from /usr/lib/libQtGui.so.4
#19 0x04c1bc79 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#20 0x04c1c0ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#21 0x07a59d53 in QDialog::exec() () from /usr/lib/libQtGui.so.4
#22 0x08189f18 in _start ()

Reported using DrKonqi