I have a new washing machine. My house is 10 years old. It was connected to the hot and cold water (which are fixed) with brand new hoses. When I set the machine on warm water, a jack hammer noise comes out from the back of the machine. The hot water starts coming out and when it tries to mix with cold to form the warm water, that's when the jack hammer noise starts. Then it stops for 3 seconds and comes out hot, then starts back up again pulling out the cold. This continues until the machine is full. The rinse cycle is always cold, so it doesn't happen. I purchased pipe banging stoppers, but it's not my pipes, it's coming from the back of the machine. I don't think my pressure is high because my kitchen sink and showers are all normal pressure. CAN ANYONE HELP ME???