My Roomba stopped charging several weeks ago, and I kept not getting around to calling. Finally, today I stayed home a little longer so I could get it dealt with... before the one-year warranty expires next month!
The support rep suspects the charger is bad, because even though its light stays on steadily, the charging base's "Docked" light blinks when it's plugged in. Since I tested the charger by plugging it directly into the Roomba, too, the Roomba is probably also now toast. So, I need to send all three pieces (but keep the battery) back to them, and they'll send me replacements. No, I shouldn't use the box it came in, because the shipping carriers don't like them. I should use a plain brown box so the shipping label is easier to find.
My instinct is that the product will have the best chance of reaching them intact if it goes back in their nice fitted styrofoam inside their carton, but I guess it doesn't matter what shape my old unit reaches them in. They'll ship me replacement stuff anyway.