There are a few frames added to the Facial Morph editor that add to your custom morphs even though in the animation bar it states "current frame"

If this is done on purpose so users can expand there facial morph library from existing facial animations, a suggestion then: -maybe when creating viseme for the first time (empty morphs) there should be a checkbox users can have set to automatically zero out all morphs because reset doesn't seem to do that and for me, if reset did actually work, I don't always remember to include reset to zero out all the morphs so the previous animation wont corrupt the new viseme morph. When the previous animation does interfere, it adds changes to the CC4 extended or standard area. I usually have to start over, set the character in T-pose, then enter facial profile editor to create correct morphs.