The diagnostics machine wracked its electronic brain but was unable to solve the mystery of the silent stereo. So Lexus did things the old-fashioned way and got a bloke to drive the car for a few days. That did the trick, and the 30 noiseless minutes at the start of most morning trips was traced to an intermittent fault with the amplifier.

A new one had to be sent over from Japan, which took two weeks, during which time we were loaned an IS250 auto – very smooth and quiet, but utterly devoid of the gutsy, growling glory of the IS-F.

The rejuvenated radio isn’t the only change. Although I forgot to mention it when the IS-F was collected, the missing towing eye cover was also replaced. I’m still not convinced that the keyless entry system is working as it should, though – it just doesn’t seem sensitive enough, especially at the boot, which refuses to open unless you’ve practically shown the key to the all-seeing video eye of the reversing camera.

This month has also seen Lexus build quality put to a stern test. Longleat’s monkeys managed to do no more than bend the plastic roof strips, but then I’m not sure their hearts were in it – the ruthless Rhesus Macaques had just ripped a Rover 400 to bits, even managing to extract a wheelarch liner before the wardens stepped in.

Can’t say whether they noticed that the wide tips of the IS-F’s stacked exhausts are fakes, but I have and it’s bugging me. About the only thing about this car that is, though.