Fruit flies driving me nuts! [View all]

I moved into a new house, rancher with a basement, this past summer. Since the weather got cooler in Baltimore, i've been plagued by fruit flies in my kitchen, and sometimes in the living room and bathroom. I've put out simple DIY traps that have worked, but more keep showing up and i have no idea where they're coming from!

There was no sign of eggs and larvae in the garbage disposal. Since I could not see the drain, I poured some bleach and hot water down it. The cabinet under the sink is dry. The entire kitchen is dry!

They must be breeding somewhere. Does anyone have suggestions on where i should look?