What is the water pressure like on the other taps in the house? If the pressure is good then you may have a faulty water inlet valve. Sometimes they don't open fully. Try changing it. Also ask your appliance dealer if he can supply a low pressure hose. These usually have a slightly larger bore and allow a little bit more water to pass through. Check the water pressure first, if ok then change the valve. If not ok then try the low pressure hose.
Lincoln Appliance NZ, November 2008