A method for making a purchase from an electronic device using an ear piece may include receiving audio information at a microphone of an ear piece, wherein the ear piece is made of a housing and a short range transceiver disposed within the ear piece. With such circuit, if the optical disk drive reads a poor-quality disk on which, in terms of signals, LPP-like noises are caused by a defect of a land area, it is possible to increase the noise immunity and LPP detection accuracy of the optical disk drive so that the optical disk drive is capable of successfully detecting LPP without fail. The cell configuration generation index represents a set of cell information parameters deemed current for a specified cell by a control node.