Probably caused by inlet valve not opening fully. Quite a common fault. Replace the water inlet valve to correct the problem. First of all, check both ends of the fill hose for any filters that may be blocked. Even check the filter which is visble inside the fill valve once the hose is removed. This filter can be pulled out with a pair of pliers to clean. If no blockages found then replace the valve with a new one.
Lincoln Appliance NZ
January 2009