LOL! – I posted about this 2 years ago, thought it was me going mad, seems it only affects some systems. Finally traced it to when I used the drop down in the viewer to get a generator but getting a generator from the effects menu then it didn’t then happen. Since upgrading to 10.8.3 (I’m not going any further on my FCP7 system) it’s disappeared and not happened now for several months.
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