@antinn
Brian told me that one of his bugbears was the amount of carbon fibre fragments through most of the cartridges in for rebuild - visible with microscope. I have never been able to reconcile this with many top end cartrdige manufacturers that I respect who deliver cartridges complete with carbon fibre stylus brush.
Brian also told me the excessive use of record preservatives/liquid stylus fluids was quite common and it would wick up the cantilever and literally gum up the works.
Are you sure the tips of the CF brush have not fractured? Pieces 5 microns in length and 7 microns wide would not be visible but could be audible.You may be interested in feedback I had many years ago with Brian Garrott, of Garrott Bros fame - they produced cartridges and also rebuilt/retipped all manner of exotic cartridges.
Brian told me that one of his bugbears was the amount of carbon fibre fragments through most of the cartridges in for rebuild - visible with microscope. I have never been able to reconcile this with many top end cartrdige manufacturers that I respect who deliver cartridges complete with carbon fibre stylus brush.
Brian also told me the excessive use of record preservatives/liquid stylus fluids was quite common and it would wick up the cantilever and literally gum up the works.