OK, i have done a search on this and i have not managed to come up with an answer, my Rappy 30 has developed the silly ability to nod at me while in a hover.
This is something new that was not there the last time i went out flying - last week, and i have not changed a thing! Most of the posts i seem to point to head speed being to low, i am currently running 1950, so i dont think this is the issue.
Where else can i look to track this problem down

when was the last time you changed the dampeners?

It has been a while, 20 hours flying time ago.

might want to invest in a new set and/or lubricating what you have.

I had a similar thing. In my case my dampeners were to blame. I had the CarbonExtreme dampers, which were very hard. They were fine for the first while, then I rebuilt the head to install an upgrade to the flybar carrier and this seemed to disturb the dampers. The heli just nodded like the Churchill dog.

I've replaced them with the TT red dampeners and I've noticed it has just recently started nodding very slightly again under light cyclic.

Like z11355 says, try changing or refitting/lubricating the dampeners, or alternatively going to softer ones if poss.

Loz

If your wings are travelling faster than your fuselage, you're in a helicopter, therefore unsafe