Well i start kaffeine with --graphicssystem opengl because others dont deliver video output:

$ gdb --args kaffeine --nofork --graphicssystem opengl
GNU gdb (GDB) 7.0-ubuntu
Copyright (C) 2009 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /usr/bin/kaffeine...(no debugging symbols found)...done.
(gdb) run
Starting program: /usr/bin/kaffeine --nofork --graphicssystem opengl
[Thread debugging using libthread_db enabled]
using visual class 4, id 2d

(<unknown>:16406): Gtk-WARNING **: Im Modulpfad »ubuntulooks« konnte keine Themen-Engine gefunden werden,
[New Thread 0x7fffdf927910 (LWP 16410)]
[New Thread 0x7fffde3de910 (LWP 16411)]
[New Thread 0x7fffd97cb910 (LWP 16412)]
[Thread 0x7fffd97cb910 (LWP 16412) exited]
[New Thread 0x7fffd97cb910 (LWP 16413)]
[Thread 0x7fffd97cb910 (LWP 16413) exited]
[New Thread 0x7fffd97cb910 (LWP 16414)]
[New Thread 0x7fffdd5c6910 (LWP 16415)]
[New Thread 0x7fffd4fc9910 (LWP 16416)]
[Thread 0x7fffd4fc9910 (LWP 16416) exited]
[Thread 0x7fffdd5c6910 (LWP 16415) exited]
[Thread 0x7fffd97cb910 (LWP 16414) exited]
[New Thread 0x7fffd97cb910 (LWP 16421)]
[New Thread 0x7fffdd5c6910 (LWP 16422)]
[New Thread 0x7fffd4fc9910 (LWP 16423)]
PB Sample buffers: true 
hijackWindow() context created for Kaffeine(0x8ec9c0, name = "MainWindow#1") 1 
hijackWindow() context created for KMenuBar(0x93f240) 2 
hijackWindow() context created for KToolBar(0x9d3a80, name = "navigation_bar") 3 
hijackWindow() context created for KToolBar(0x91f3d0, name = "control_bar") 4 
hijackWindow() context created for QWidget(0xefb800) 5 

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff5ddf23c in qt_x11Info (pd=0x9d3a90)
    at painting/qpaintdevice_x11.cpp:92
92	painting/qpaintdevice_x11.cpp: No such file or directory.
	in painting/qpaintdevice_x11.cpp
Current language:  auto
The current source language is "auto; currently c++".
(gdb) thread apply all bt

Thread 11 (Thread 0x7fffd4fc9910 (LWP 16423)):
#0  0x00007ffff45193c2 in select () from /lib/libc.so.6
#1  0x00007fffe387d725 in xine_usec_sleep () from /usr/lib/libxine.so.1
#2  0x00007fffe38627e9 in ?? () from /usr/lib/libxine.so.1
#3  0x00007ffff31c6a04 in start_thread () from /lib/libpthread.so.0
#4  0x00007ffff45207bd in clone () from /lib/libc.so.6
#5  0x0000000000000000 in ?? ()

Thread 10 (Thread 0x7fffdd5c6910 (LWP 16422)):
#0  0x00007ffff31cb5a9 in pthread_cond_wait@@GLIBC_2.3.2 ()
   from /lib/libpthread.so.0
#1  0x00007fffe3865983 in ?? () from /usr/lib/libxine.so.1
#2  0x00007ffff31c6a04 in start_thread () from /lib/libpthread.so.0
#3  0x00007ffff45207bd in clone () from /lib/libc.so.6
#4  0x0000000000000000 in ?? ()

Thread 9 (Thread 0x7fffd97cb910 (LWP 16421)):
#0  0x00007ffff4514373 in poll () from /lib/libc.so.6
#1  0x00007fffdd9d9cbe in ?? ()
   from /usr/lib/xine/plugins/1.26/xineplug_ao_out_alsa.so
#2  0x00007ffff31c6a04 in start_thread () from /lib/libpthread.so.0
#3  0x00007ffff45207bd in clone () from /lib/libc.so.6
---Type <return> to continue, or q <return> to quit---
#4  0x0000000000000000 in ?? ()

Thread 3 (Thread 0x7fffde3de910 (LWP 16411)):
#0  0x00007ffff4514373 in poll () from /lib/libc.so.6
#1  0x00007ffff1bf136c in ?? () from /lib/libglib-2.0.so.0
#2  0x00007ffff1bf16b0 in g_main_context_iteration ()
   from /lib/libglib-2.0.so.0
#3  0x00007ffff50c81a6 in QEventDispatcherGlib::processEvents (this=0xa7f560, 
    flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:327
#4  0x00007ffff509e532 in QEventLoop::processEvents (
    this=<value optimized out>, flags=DWARF-2 expression error: DW_OP_reg operations must be used either alone or in conjuction with DW_OP_piece.
) at kernel/qeventloop.cpp:149
#5  0x00007ffff509e904 in QEventLoop::exec (this=0x7fffde3de000, flags=DWARF-2 expression error: DW_OP_reg operations must be used either alone or in conjuction with DW_OP_piece.
)
    at kernel/qeventloop.cpp:201
#6  0x00007ffff4fb66cb in QThread::exec (this=<value optimized out>)
    at thread/qthread.cpp:487
#7  0x00007fffe3aaf56e in ?? ()
   from /usr/lib/qt4/plugins/phonon_backend/phonon_xine.so
#8  0x00007ffff4fb9445 in QThreadPrivate::start (arg=0xa7f520)
    at thread/qthread_unix.cpp:188
#9  0x00007ffff31c6a04 in start_thread () from /lib/libpthread.so.0
#10 0x00007ffff45207bd in clone () from /lib/libc.so.6
#11 0x0000000000000000 in ?? ()

---Type <return> to continue, or q <return> to quit---
Thread 2 (Thread 0x7fffdf927910 (LWP 16410)):
#0  0x00007ffff31cb82d in pthread_cond_timedwait@@GLIBC_2.3.2 ()
   from /lib/libpthread.so.0
#1  0x00007fffe3854c91 in ?? () from /usr/lib/libxine.so.1
#2  0x00007ffff31c6a04 in start_thread () from /lib/libpthread.so.0
#3  0x00007ffff45207bd in clone () from /lib/libc.so.6
#4  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7ffff7fc4750 (LWP 16406)):
#0  0x00007ffff5ddf23c in qt_x11Info (pd=0x9d3a90)
    at painting/qpaintdevice_x11.cpp:92
#1  0x00007fffef01adc1 in QGLContext::reset (this=0x1a1fcb0) at qgl_x11.cpp:617
#2  0x00007fffeefe881b in ~QGLContext (this=0x1a1fcb0, 
    __in_chrg=<value optimized out>) at qgl.cpp:1541
#3  0x00007fffeefdfec8 in ~QGLWindowSurface (this=0x7381f0, 
    __in_chrg=<value optimized out>) at qwindowsurface_gl.cpp:260
#4  0x00007ffff5df6988 in ~QWidgetBackingStore (this=0x95d290, 
    __in_chrg=<value optimized out>) at painting/qbackingstore.cpp:829
#5  0x00007ffff5c75b54 in QWidgetPrivate::deleteExtra (this=0x93f8f0)
    at kernel/qwidget.cpp:1503
#6  0x00007ffff5c762ad in ~QWidgetPrivate (this=0x93f8f0, 
    __in_chrg=<value optimized out>) at kernel/qwidget.cpp:227
#7  0x00007ffff5ff620b in ~QMainWindowPrivate (this=0x93f8f0, 
---Type <return> to continue, or q <return> to quit---
    __in_chrg=<value optimized out>) at widgets/qmainwindow.cpp:72
#8  0x00007ffff50b64f9 in ~QObject (this=<value optimized out>, 
    __in_chrg=<value optimized out>) at kernel/qobject.cpp:857
#9  0x00007ffff5c7bac8 in ~QWidget (this=0x8ec9c0, 
    __in_chrg=<value optimized out>) at kernel/qwidget.cpp:1380
#10 0x00007ffff6b91185 in KMainWindow::~KMainWindow() ()
   from /usr/lib/libkdeui.so.5
#11 0x000000000047417c in _start ()
(gdb)