This sounds like the field dominance setting is set to Field 2 (I believe that's the default). These cuts are a single frame, not a dissolve. It's showing the even fields from one camera angle, and the odd fields from the second camera angle. This is pretty normal when working with interlaced video. If you don't want this to happen, you can change the setting to Field 1 (that's what I've done, as it made life easier if a shot needed to be replaced from ISO).
#Carbonite