Just to update , I changed the hose pipe which goes from the hose reel to the trolley unit ( cheap garden hose) .
I went to Window cleaning warehouse in Liverpool and replaced it with some black hose ( a lot stronger it seems) .
This was at the beginning of the month, since then , iv not had any 'bits' on the glass 🤔
Maybe the garden hose was disintegrating , it did bulge in places .
Anyways , it's a cheap fix so if your getting bits on the glass , try this first 👍