@GeoMax: Had this problem once already 2 weeks ago. Watch out for group tracks which all of a sudden changed type from group track to a normal track... In the mixer you can see this easily at the fader caps colour... This was the problem in one of my projects - once the misleaded track had been deleted, everything went back to normal...
DAW 1: Commodore C64, 64 k, Windows Basic, Cinch out, Datasette and 1541 Floppy
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DAW 3 : Dell Precision M4600, i7, 16 GB Ram, Win 7 Pro x64, Cubase Pro 8 x64, Dante Virtual Soundcard
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