Hi everyone I need some help with my setup. I currently have a Macbook Pro, 2x B&W 685s, Polk Sub and a Pioneer VSX-810 receiver. I am sending audio through mini-displayport to HDMI connected to the Pioneer receiver. Then I have the standard connections for speakers and sub. I am only using this setup for audio so all other ports on the receiver are empty. I would like to upgrade my receiver (and later Sub) but I am not sure the best way to go. I know I will need a DAC but not sure which one would be best. I would like to keep the budget under $600 for everything. But if something is worth spending more please let me know.