2007 MCS automatic problem
 

I have a 2007 Mini Cooper S with automatic. It hunts between 1st and 2nd when accelerating. Really annoying and sure it will tear trans out of car. Took to dealer and they did not offer any suggestions. Just wanted to do trans service for $750.00 but did not know if they would find problem. They then suggested that I could replace trans for $3000.00. Crazy!! Anybody have any knowledge of this problem and suggestions to fix? It sems like a bad sensor but never could get dealer to admit it.