Not knowing in what kind of space the action takes place, it’s hard to make detailed recommendations. However, it’s probably a matter of level and eq (and maybe pitch) that is making those cues stand out – not reverb. There are some plugins and native programs (Ozone 4, Match EQ in Soundtrack Pro and others) that can measure the eq of the original track and apply it to the new one. Listen carefully to the tracks that don’t work and try to decide what quality is different. Too much bass, not enough, too loud, to soft. Keep your ambiance track underneath, but before you lay in the dialogue, listen to be sure the background matches. If not, fix that first, then lay in the voice. Sometimes it’s a pitch issue. There are plugins in FCP that affect pitch. Try that. It sounds like you’re on the right track.
John
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