I just bought a dvr510 from a friend, I am going to sell it on ebay. The 510's I've seen on ebay say things about there being a zero balance on the account that the dvr was activated on. Is there a way to check to see if the 510 I bought came from an account that has a zero balance on it? If it didn't and I sold it on ebay and someone bought it and plugged it in would it not work??