If you have DAC with some problem (such as sound distortion in one channel) - it may help you to understand principles of this DAC functioning and to track malfunction to the failed component or failed solder joint.
Look at the photos of the actual module - schematic is only for PCB on the photo, with Burr-Browns DAC7541 digital-to analog converter ICs. D20400 has some different versions, so if you have other version - schematic may not match your device. Buy with confidence.
Note:
Reference designators (such as R1, C1, U1) are random as they were not marked on my PCB.