After upgrading from Jaunty to Karmic, I had this problem too. After eventually tracking down this bug report (took me a while to work out that mythtv was to blame!), I followed the instructions from comment #17, and that fixed the problem for me.
After upgrading from Jaunty to Karmic, I had this problem too. After eventually tracking down this bug report (took me a while to work out that mythtv was to blame!), I followed the instructions from comment #17, and that fixed the problem for me.