When I use the hot water in my six month old home it has started whistling and the pressure is not as good as it was. The separate shower is fine as is every other tap in the house. What can the problem be?

Does every hot tap in the home cause the same sound? Where do you live and is there a new home warranty?

No only the bathroom hot water tap. I live in Bonney Lake Washington and there is a home warranty.

Does every hot tap in the home cause the same sound? Where do you live and is there a new home warranty?

No, only on the sprayer on the kitchen sink. I live in Missouri and no home warranty