i have studion 1 2.5 pro and 24.4.2. some songs in 2.5 pro i can use 24.4.2 faders other songs can not. what's wrong?

The StudioLive mixers will not work as a controller with Studio One. You can use Universal Control to control the faders, but not Studio One. You can download the latest version of Universal Control from the following link:

http://www.presonus.com/support/downloads