My DVD player and Freeview box both have phono (RCA) audio outputs. Both also have digital outputs (Freeview co-ax, dvd optical). My amp has the same inputs but only the phono activate the auto-switching of devices. To use the auto-switching I need to connect phono-to-phono but can I also use the digital connections at the same time, to give the best sound output, or will it cause problems? If not will there be a discernable difference in sound quality if I just connect with phonos.