While driving, if some whining noises is heard, here's how to diagnose them
Case 1
If the car is in Park or Neutral, and the whining noise is still present, gearbox needs to be checked
Case 2
If the car is moving and whining noise only occurs when accelerator pedal is stepped [ whining may be more pronounced especially above certain speeds eg >60km/h] and goes away when feet is off the accelerator, the rear differential needs to be checked
Case 3
If whining is constant throughout the drive and the sound is more pronounced when swerving left and right, the front wheel bearings need to be checked.
Case 4
If car is in Park or Neutral with ignition switched off and the whining ensues, you probably have to find out soon what the children or missus needs.