1.7 "Edit Sequence" option 5 drama

in 1.7, I'm having some issues when I copy a Sequence (option 5 in Edit Sequence mode). In 1.6 and earlier versions, Id use say 21 tracks to make up the whole song, and have say 19 of them muted when begin to to craft the song, sequence 1. I'd copy that sequence (option 5 on the Edit Sequence) and make sequence 2. With 1.7, when I add changes via unmuting a few more tracks to add to sequence 2, it also changes them on sequence 1. What gives?

Again in 1.6 and earlier, I would normally mix all my levels with all of my tracks (21 in this case) playing at once in the Track Mixer screen. Once that is done, I mute all the tracks except for a few I want to use for this first sequence, now I'd have the first sequence I'd use in Song Mode. I'd copy that sequence in Main mode via the Edit Sequence screen and choose option 5, "Copy a Sequence". I would then go to that new sequence in the Track Mixer screen again, with this new sequence. I'd unmute a few more tracks I wanted to add to that next sequence and so on. Now in 1.7, the whole process works except for now, when I add changes to that second and new sequence, it changes it on the first sequence too. Is there a way to turn that feature off, or is it a bug? Whats a global mixer? Is this the cause?