Frankie1g

My book says maximum pressures for reduced tire wear

Hi my 2015 ml4 30k q7.has an odd fault The drivers mmi can normally be changed by pushing the reset button on the right stalk. It changes the digital speed, navigation etc. But sometimes.it does not change at all. Some times it acts like the rocker switch on the end of the stalk. And cycles through the modes as the end rocker switch does Sometimes it works perfectly. Is this a software issue? Or have anyone see this before ?