Pressing GO modifies the show?

With a newly-loaded show (no manual changes since opened), we have some cues where the following occurs: Load the cue so it is pending, then press GO. The act of pressing GO somehow modifies the show, since the show name is now annotated with an asterisk indicating it has changed since last being saved. How can this possibly happen? We did modify some of these cues in Blind to ensure that channels with NPs were removed from them.
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