I have an Oppo 105 as well and I'm basically using it as my digital hub/transport and send all to an Audio Research DAC8 and couldn't be happier with the ease of use as well as sound quality.
Should I sell my DAC
I have the upgrade itch and am thinking of selling my OPPO 105 player. Currently I am using the player’s fantastic USB dac to play Tidal web player in my office driving powered KEF speakers. No need for Blu ray anymore and don’t use the unit as transport. If I sell the player for $650 - is there a better USB dac than OPPO 105 in the $1100 range? I prefer advice and recommendations from folks that have heard the OPPO USB dac.