This is from the SONAR Home Studio 6 Help files:
Unlink Clips dialog
When you right-click a selected group of two or more linked clips and choose Unlink from the popup menu, the Unlink Clips dialog box appears.
This command lets you specify when unlinking selected linked clips whether to form a new, different linked group or to make the clips completely independent.
To stop this from happening in the future, uncheck the Link Clips box in the copy/paste dialog.
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