Please help me determine what is wrong. After using water in the house for a while, we gradually begin to smell an odor that I think smells like sweet cooked hamburger meat, or a slightly burnt beef roast. It is strong & permeates the whole house, and lingers long into the night. It is sickening to me. I spray and it does no good. My husband says it;s not the septic, so what is it? Our house & sewer & septic is 6 years old. What do I need to do? We've not yet pumped out the tank, do you think that should be done to alleviate the odor? Thanks...Alyce Kirby