Sold a Panasonic RX DT690 a few weeks ago on epay, Radio was tested and fully functional when i shipped it. Now slowly but surely buyer is starting to send emails pointing out this is wrong and that is wrong. Was insured for the full amount with Fedex. I have this ucky feeling that buyer is about to pull some crap on me wanting a full or partial refund. My auction states sold as is with no returns. Should i be worried since it has insurance coverage?