ORIGINAL: alfredbmor

Personally I think that it is an extraordinary situation and I would fix it for once by sanding with a very thin black sanding paper. Chances are that this rubbish could generate a moderate vibration that can cause that the back bearing wear sooner. I have the same engine and I will check the same situation, mine has less than 10 flights but I have not seen anything wrong, either way is a good time to check it up.