Well the same as you ottoman, when i drove the dealers demo in feb that didn't have a noise from the gearbox, when i drove it again in march (the same car)it still didn't have the noise, when the dealers senior tech drove the cars back he couldn't hear the noise, when i drive the cars i could tell straight away.
I just wish the problem is sorted quickly as at the moment i am paying for a new twingo and currently driving an 07 plate clio courtesy car, if i wanted to drive a clio i would of bought one in the 1st place!!!!
I don't think the dealers don't want to repair your car They just dont know what the problem is and if they take it to bits and it's still there ...
I will try and have another drive in a Twingo in the morn..
Does this noise appear from cold/hot/ any particular gear road surface speed ?