So your drivers display is the full digital one w/analog speedo and tach? If so, haven't seen anyone on these forums mention this before. Must be unique to your car. Sounds like a possible loose connection? But that's a safety issue. Call Kia CS, tell them dealer can't fix and you are going to file a complaint w/NHTSA:
https://www.nhtsa.gov/report-a-safety-problem#index
