Probably dying, could be the cable, but more likely the stepper motor. The whole unit is easy to remove and replace. But they are expensive these days. Not heard of them being easily repaired.
I had the same problems a few weeks back. mine turned out to be a split is the side casing. Tried to repair, but moving it made things worse and superglue seemed to have little effect and messy. Ended up scrapping mine and going a different route.
If it does turn out to be split plastic it may be worth trying this new technology