Thank you Mike.
Reg is OY 59 ZTJ, 6 speed manual box.
Started it up this morning, NO tapping noise.
Checked the oil level on dip-stick, right on the max level (all 'dimples' on the end wet with oil. I rotate the dipstick two turns before pulling it out.
Car has the general vibration from approx 3K rpm.
Took it to the dealer who has serviced it several times and went for a ride to demo the vibration. He said there was one and had no idea of the problem...
Car drives as usual in touring and sport mode, all dash lights are clear.
It is as if the exhaust is on the chassis and the vibration can be felt in the wheel, the foot well etc as well as heard. Engine lower mounts all look sound.
Maybe my SRi has the DMF?
The clutch action has never been smooth with a decernable 'bounce' when changing to 2nd from 1st under acceleration.
today no noises just that vibration.
Now thinking of getting a Skoda Superb.
Looks like I've bought a Skoda Superb Tour de France special edition. Drives 'superbly' as the joke must go. Nice drive, smooth as can be and will tow my racing car a treat (as the Insignia has done for 4 years). Will be sad to see the SRi go, it has been fault-free all my ownership until this episode, but i must have a dependable regular road car.
Back to an oil burner, but this Skoda is SO quiet, untrue, smooth torque and goes well when you put your foot down. Not as fast as the SRi, but I'll get used to the relaxed pace.
I can see the SRi starting to cost me and the car is worth just £5500 so soon good money after bad.
Regards, and i thank you for the details on the vibration, it all stacks-up.