@glennewdick yes, that makes sense, up to a point. If the DAC was the upgradeable DA2, as it is in several of their other products, there would definitely be no need for digital out. But how long before the built in DAC is obsolete to new choices? So, either a digital out to salvage the unit as a streamer only, or an upgrade path for the DAC would have made more sense, IMHO. The MDA200 has the DA2.
P.S. LOVE your Sansui Tu 9900!