Speicherzugriffsfehler (Speicherabzug geschrieben) - memory-access-error (core dumped)

lately I was searching for a graphic library to use with python. While testing panda3d and pyglet I could not even run the examples. I don't exactly know if this is due to the same problem, but it seems to me that is has a common issue. Unfortunately I'm not experienced enough to solve this issue and therefore need some help.

I got the following errors:

pyglet:

Speicherzugriffsfehler (Speicherabzug geschrieben)

running this code:

from pyglet import window
window = window.Window

panda3d:

Starting the game.
Known pipe types:
  glxGraphicsPipe
(all display modules loaded.)
:display:x11display(error): BadRequest (invalid request code or no such operation)
...
ca. 140 times
...
:display:x11display(error): BadRequest (invalid request code or no such operation)
:display:glxdisplay(error): Could not find a usable pixel format.
:display:glxdisplay(error): No GLX context: cannot open window.
:display:x11display(error): BadRequest (invalid request code or no such operation)
...
ca. 20 more times
...
:display:x11display(error): BadRequest (invalid request code or no such operation)
:ShowBase(warning): Unable to open 'onscreen' window.
Traceback (most recent call last):
  File "Tut-Asteroids.py", line 13, in <module>
    import direct.directbase.DirectStart
  File "/usr/share/panda3d/direct/directbase/DirectStart.py", line 4, in <module>
    base = ShowBase.ShowBase()
  File "/usr/share/panda3d/direct/showbase/ShowBase.py", line 244, in __init__
    self.openDefaultWindow(startDirect = False, props=props)
  File "/usr/share/panda3d/direct/showbase/ShowBase.py", line 880, in openDefaultWindow
    self.openMainWindow(*args, **kw)
  File "/usr/share/panda3d/direct/showbase/ShowBase.py", line 916, in openMainWindow
    self.openWindow(*args, **kw)
  File "/usr/share/panda3d/direct/showbase/ShowBase.py", line 671, in openWindow
    raise StandardError, 'Could not open window.'
StandardError: Could not open window.
[xcb] Unknown sequence number while appending request
[xcb] Most likely this is a multi-threaded client and XInitThreads has not been called
[xcb] Aborting, sorry about that.
python: ../../src/xcb_io.c:161: append_pending_request: Zusicherung »!xcb_xlib_unknown_seq_number« nicht erfüllt.
Abgebrochen (Speicherabzug geschrieben)

running the Asteroids example.

(I am using Ubuntu 12.04 and python 2.7.3.)

Info: "Speicherzugriffsfehler (Speicherabzug geschrieben)" roughly means "memory-access-error (core dumped)"

Thanks for your help, Max

P.S.: Every other post I found regarding this topic was about C/C++ mostly having problems with pointers / direct memory access. Since I am only using basic examples something must be wrong with the libraries - which I doubt - or I have a wrong package configuration somewhere / a broken driver. Another option would be a problem with the window creation itself which I unfortunately don't know enough about either. Please tell me if I need to post more information.

Solution

After I realized some other programs (e.g. blender) stopped running, too, I reinstalled the amd drivers and now everything runs fine.