I have a FD-NEX adapter that fits perfectly on my A7, but will not fit on my A7S (it's so tight that I feel like I'm gonna break the mount if I keep applying force. I use an FE Rokinon 14 that fits both bodies no problem. I've checked the mount on the A7S vs the A7, and to me they look the same, and the A7s doesn't look like it has any debris, or misaligned contact points, etc. Anyone know what could be going on? I'm mounting the adapter onto the A7S the exact same way I am with the A7. I can't really tell the difference between the mount tabs on the adapter vs the tabs on the Rokinon. Unfortunately I don't have any native FE mount lenses to test.