Wrong aspect ratio

From Miro User Documentation

Issue: The aspect ratio of the video is wrong!

Solution: Usually xine discovers the screen aspect ratio by querying the X-server and then adjusts the video automatically to make it look right. However, if that doesn't work try pressing "a" to manually change the aspect ratio.

If you have a wide screen monitor, make sure the X-server is correctly configured. The X-server must know the physical size of the screen, which is independent of the resolution being used.

• For X.org, the screen size should be set in the "Monitor" section in the file /etc/X11/xorg.conf, as in the example below:

  Section "Monitor"
     Identifier   "Monitor0"
     VendorName   "Monitor Vendor"
     ModelName    "DDC Probed Monitor - ViewSonic G773-2"
     DisplaySize  320	240
     HorizSync    30.0 - 70.0
     VertRefresh  50.0 - 180.0
  EndSection

• For XFree86, the filename is normally /etc/X11/XF86Config.

Where DisplaySize specifies, in millimeters, the physical size of the monitor's picture area.

Original Source: http://xinehq.de/index.php/faq#ASPECTRATIO
Forum thread: http://www.getmiro.com/forum/comments.php?DiscussionID=258&page=1