Cache at rendering flickering and transparent

[Alexx31]

Hello,

finishing a long project I'm rendering a long sequence with multiple tyCaches, now it starts flickering.
The same caches once worked already in render.

While I start my examination, maybe there are some known tips or caveats?

EDIT: I am using tyCache with retimer.
It seems to go with round nearest frame... which leads then to unsmooth movements of falling objects... 
So it seems actually better not to use retimer?

.. still investigating...

Thanks