Problem unlinking clips in ADD and Sonar Platinum

I'm having a problem unlinking clips in the sequencer for ADD. It seems to work fine with first one I unlink. But after that every time I try to put in a roll or change to a chorus or bridge, it just keep changing the first one I did. I've seen tutorials that said you have to hit the ALT button when you split it, and others that say you don't. There doesn't appear to be any info in the help files. Anybody have any ideas. I would appreciate it.