When You Flush The Toilet After It Starts To Refill With Water
A Loud Squelling Sound Coming From Out Of Hot Water Heater.
Any Ideas? Just Started Doing It,

Air in water lines can make noise when it goes through valves. If it's air, the problem will usually take care of itself as the air goes through the system. You can get air in the lines when there has been work done on the pipes either in the house or down the road.

Bad valves can cause noise when water goes through them. You can usually locate the valve by pinpointing the noise. Since it just happens when you flush the toilet it would seem it would be the cut off valve or the valve in the tank.

Turn the water off to the water heater only and see what happens when you flush.

thanks ill try it tonight and see what i come up with. Much apprciated.