Big time rookie making mould, so perhaps this might come as a stupid question.

I'm trying to create the shape of my silicone mould, from a piece of wood.
The piece of wood was carved on a CNC and I then polished it to a smooth surface with sanding discs.

I created my mould box > placed my wood piece > and poured in my silicone rubber (after a trip into the degassing chamber)

The shape of the silicone mould came out very nice, however im experiencing the following issue:
Due to the nature of the wood, the grain in the wood would have small "pockets" (not sure what you would call it),- like tiny tiny (randomly) thin lengthy spots following the grain (which you ofcourse wouldn't see with leveled solid material) that transfers to the silicone mould.

Is there anything I can do to prevent these "engraved grain" spots to transfer to the silicone mould? Like polishing the wood in some special wax (that would fill/create a leveled surface) or similar before making the silicone mould?