It needs a clean/lubrication. I've had this a few times with Campag shifters, and a good clean of the internals (normally via a few judicious blasts of GT85), followed by a quick lube usually sorts it out. A new cable can help too.
@andyp started
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It needs a clean/lubrication. I've had this a few times with Campag shifters, and a good clean of the internals (normally via a few judicious blasts of GT85), followed by a quick lube usually sorts it out. A new cable can help too.