The Fragrant MrsP was having some issues with changing gear, clunking on two cogs in particular and also a creak when going up hill, everything worked fine and dandy on the stand, but no so when riding.
We both ummmed and scratched heads, we cleaned the cassette, cleaned and checked the chain, we checked the BB, couldn’t find the cause.
Then by accident I discovered the the quick release skewer was a bit loose, not falling out the dropouts loose, but not very tight.
Took the bike off the stand, made sure the wheel was set in, tightened up the QR, test ride of ten miles. Sorted.
Sometimes the bleeding obvious is staring at you and you don’t see it.