The upgrade offered requires you to send in your BDP-83 at your cost. Oppo will replace the audio board that includes the upgraded DAC's, the power supply board and the rear panel that includes an RS232 port. The cost is $299 plus shipment to Oppo. The clock will reset and extend the original warranty.
The new DAC's are designed to specifically improve analog audio performance. The upgrade is not recommended for those using HDMI for both video and audio.
The link is: http://www.oppodigital.com/blu-ray-b...adeOption.aspx