Is your AE up to date? How about your GPU drivers? Did you clear the disk cache? There have been problems with ghost images reported in previous builds of AE. Without more info that's about all I can tell you.
I have AE CC 18.104.22.168. I think it's up to date.
I'm not sure about the GPU drivers.
But I emptied the disk cache and emptied the conformed media database & cache.
It seem to have worked.
Thanks a Lot!