It's an expensive cassette with less than 3,000km on it. Not changing it. No stiff link.
Still sound like you may need to change it.
Forgive me for the barrage of question; what was the chain wear when you check it with a chain wear tool?
@Dammit started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
It's an expensive cassette with less than 3,000km on it. Not changing it. No stiff link.