One simple solution is to get a DAC with optical input rather than the Halide which has only USB.
The Airport Express has optical output so the setup would be MacBook > Airport Express > DAC with optical input > Speakers.
There are lots of DACs with optical input in the price range of the Halide, one good one is the Musical Fidelity V-DAC but there are lots of others. Get a Sonicwave glass optical cable and a Toslink-mini Toslink adapter from Amazon for $30 if you want to top everything off.
The Airport Express has optical output so the setup would be MacBook > Airport Express > DAC with optical input > Speakers.
There are lots of DACs with optical input in the price range of the Halide, one good one is the Musical Fidelity V-DAC but there are lots of others. Get a Sonicwave glass optical cable and a Toslink-mini Toslink adapter from Amazon for $30 if you want to top everything off.