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The same thing happens to me. Luckily, whenever it happens it's not really noticeable, but it takes the weirdest sounds from random sections of the clip. I'm interested in a fix as well - on a side note, I just ordered FC Express! :D:apple::apple::apple::apple::apple::apple::apple:
 
workaround

I've found that if you select the transition and use the "Extract Audio" command to remove any audio from the transition, the stuttering goes away.
 
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