Our water heater grumbles after we use hot water. It's really loud upstairs because the water heater is upstairs in our attic. It gets so loud that it wakes our child. Our master bath makes a loud fog horn noise after we flush it. It sounds like the Jaws music. It is super loud. Could these issues be related.. Need answers in Houston, TX, PLEASE!

Could be.

Step #1:

Get a water pressure gauge and check the pressure. Amazon.com: Rain Bird P2A Water Pressure Gauge: Patio, Lawn & Garden (http://www.amazon.com/Rain-Bird-P2A-Water-Pressure/dp/B00004RACK/ref=sr_1_1?ie=UTF8&qid=1359357788&sr=8-1&keywords=water+pressure+gauge)