Asset Quantity Not updated after GRS

Hi,

Does anybody tell me that the quantity in asset master must be updated by MM, after the GRS for the account assignment 'A'?

For our current system ECC5.0, the asset quantity was not updated at all, if the new asset was created with zero quantity and blank unit of measurement.

However, the asset quantity will be added by '1' if the new asset was created with 1 quantity and unit of measurement. In other words, the asset quantity would be appeared as '2', which is incorrect.

Is it do with the MM configuration end?

Pls advise and appreciate that.