If anyone's got any advice on how to fix this problem I'd really appreciate it: I've just put a new cassette and chain on my 2014 Ultegra Di2 10-speed. Exactly same chain length and cassette size (11-32), all was running perfectly before apart from chain wear. Now I've replaced the parts (with OEM parts) for some reason the gearing thinks that everything's one cog to the left, i.e. it only runs up to the ninth cog and stops (literally stops, refuses to attempt a shift as if it thinks it's already on the biggest cog), and running down it gets to the smallest cog and thinks it still has a cog in hand and throws the chain off (I've stopped this by adjusting the limit screws). I've tried multiple times running through the adjustment cycle from the junction box and the gears are all running perfectly apart from this problem. I've changed the cassette and chain many times on this bike and never had this problem, am I overlooking something blindingly obvious?
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