Unpleasant noises initially, but now chain is slipping off a couple of times in each ride. The limit screws are all setup properly, but I think the chain is loose and it is slipping from the worn cassette and chairing.

I normally don't mind, but it has become a safety issue for me commuting & have had to change riding style. (I usually gun it on the bigger rings, but I have to shift down earlier when coming to a potential stop otherwise risk chain coming off if I put too much force through).

Sorry if I have the terminology wrong, I normally just ride and don't really think about it... first time I have to !