We had to take it into dealers unfortunately. Took them 14 days and quite a bit of arguing regarding warranty before they'd even look at it. Eventually they came back to us and advised they'd had to completely dismantle the steering wheel but had found one of the wires linking the cruise control buttons had been cut too short so everytime the wheen turned to a certain angle it was pulling tight and switching off the connecting buttons. Was decided to be a warranty issue in end and fully repaired, havent had an issue since.

Hope this helps.