I've just had the car checked by 3 mechanics.
One mechanic said it's the transmission input shaft bearings, the second mechanic said it's the gearbox bearings, and the third mechanic said it's the clutch bearings.
The first seems more logical by saying that if it was the clutch bearings, the noice would start when the clutch is depressed, but in this case, the noise starts when the clutch is not depressed, in neutral or when accelerating at low revs.
So how do I find out what the problem is? Everyone has a different opinion and I do not want to fix what is not broken.