dbr/tvdb_api — pull request #32 by tremby (2013-03-09 23:48:01+00:00)
Title: Use thetvdb.com rather than www.thetvdb.com

The domain without the www subdomain is allegedly more reliable, giving fewer 503 errors. See http://forums.thetvdb.com/viewtopic.php?f=4&t=12909

It has helped in my case at least.