Eek. This started today. When going up hill or accelerating from a standstill (so putting a bit of load on the car) I can hear a distinctive whine. It sounds a bit like belt whine. It will only do it under load. As soon as I lift of the pedal the noise stops dead. It does sound sort of similar to when the cat went on my C55. As always it will not do it with the car stood still. Is there anything silly that springs to mind? FYI: I did have a check underneath and do not see anything caught up or being dragged. I also checked belt tension (about half an inch of play) and gave it a squirt of belt dressing.