Hi guys, just chiming in. I had this issue with my original 3135cal. I though it was normal too but it turned out to be a bad mainspring. Between 5-10 turns while winding the movement, it would make a snapping/clicking sound (as skipping). I sent the watch back to the watchmaker to inspect and he found it was the mainspring. Hopefully this can shine some light to those who encounter this problem. I've read online some claim this is normal, but it wasn't at least in my case.