I've been DJing with Ableton for a long time, a good few years, and love it. The one thing that always annoyed me was the fact that the EQ Three plugin, supposedly designed for easy DJing and Live Performance, provided one completely out of touch feature - the Gain controls for the 3 bands didn't set themselves at Unity Gain (0Db) in the '12 O'Clock' position.
But I have discovered a fix. Watch the following little screencast I've made to demonstrate how to get around this little but significant bug.
This video is taken from Paul's website, and is used by permission.