Do you have a PRV to reduce the water pressure in the house? It may be failing or failed. Do you have an expansion tank (needed if you have a PRV)? It could be waterlogged and needs to be replaced. Check the drain on the water heater and verify that the T&P valve is not weeping water. Best to check this after a big use of hot water while the tank is reheating the water and you are no longer using hot. The expansion of the water as it is heated can raise the pressure if it is a closed system if there's no provision to expand (that's what an expansion tank is for).
Get a water pressure test gauge. They're cheap (around $10). Get one with a second tattle tale hand that will indicate peak pressure. Leave it attached for 24-hours. See what the peak pressure and static, average pressure is. It should not exceed 80psi. High water pressure can cause some weird noises in plumbing and stresses the supply hoses on faucets and washing machines. Toilet fill valves are often one of the weaker shutoffs in the house, and they can make some weird noises if the pressure gets high.