No, nothing has cured it. I have spent MANY hours testing and writing various forums, (or is it fora?). E-M1 IS is useless on the scope.
It seems to be a combination of weight and focal length setting. For instance:
No IS, 8 (8 sharp out of 10 shots at 1/400)
IS on, 1
IS on, with IS set to half-press, (and waiting until the vibration stops) 3-4
700g weight (old pan/tilt head) screwed onto the camera:
IS off 0!!!! (What a surprise THAT was!!)
IS on 5
IS on with half-press 6
Old Sigma 500 mirror, no vibration and IS works.
Same with weight, vibrates and no IS
Nikkor 400 works great with and without weight, but with 2x TC301 and set to 800, vibrates and no IS. Set to 600, no vibration and IS works not bad.
Scope, IS set to about 200mm, no vibration and very light IS function. Above 200mm, vibration and no IS.
So, if it vibrates, the IS stops all together. Maybe it is a protective thing built in.
My conclusion is that the IS is only really good up to about 400mm with light weight lenses. After that, forget it. Oh well, not every car that has 280 k/h printed on the speedometer actually goes 280!
When I wrote to Oly, they told me they can only grantee the IS to work with Oly lenses. But they only make up to 300mm! To me, that is BS!