The cable may very well not be the problem. But if it is, compared to a transmission repair, it is easy and inexpensive to investigate and fix. So far, no one has volunteered any code reader information, no one has mentioned the diagnostic system embedded in the shift selector display. What I have offered up as an approach, makes sense - assuming that tait88 doesn't want to throw money at the problem.Nice.
I really hope that is the problem.