I have a Maytag washer, model number LAT9400AAW; washer is approx 14 yrs old. My problem is that the water fill is intermittent. Sometimes the water fills appropriately, other times the water stops filling, for both hot and cold water. When the water does stops filling intermittently, I hear a buzzing sound from the timer, so there is power. Could my problem be a faulty water inlet valve?

Im leaning towards a pressure switch. Check the hose conencting the pressure switch. Maybe you can try replacing the hose first, as it will be the cheapest thing to start with. Then, you can try the switch.