One other thing to try, a couple of times the cone gear for the dial right behind the shutter did not line up for me. If it gets stuck tooth to tooth (technical term) it will be enough for the dial to be intermittent. Just wiggle it and check that it lines up when you insert the camera. Good Luck,
Exactly what happened, all the cone gears and dials didn't line up; so just as you said, I just wiggled it a bit and now everything is fine !
Thanks for that,