Hi all, 2006 2.2 CDTI FR-V has the multifunction steering wheel. In the car is a Kenwood DNX5200BT SatNav DVD player, Phone double din unit. The only annoying issue is, until recently the volume up and down buttons would only work intermittently. Sometime the volume up button would lower the volume and vice versa. This past week everything has topped working. Could it be as easy as just the interface box between the radio and steering wheel going duff? Has anyone any experience of such matters? Thanks All.