Was it this you turned off? I've had it off since the beginning. I used to get the wifi unstable notification right out the box. But I shut this off. Go to settings, click wifi, hit menu key next to home button, advance, turn things off until you get it to stop. I also turned off auto switching. Which I think that's the problem if you ask me. Because it would pop up then auto switch off wifi because it was unstable. It will still switch back and forth when you leave house but it just won't switch because it thinks it's bad.
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