D1V33 can be slaved to a master clock with frequency (256fs) at max fs 48kHz. The limitation is due to the digital filter SM5842. If SM5847 is used, the Fs max can be up to 96kHz.
1. Cut the trace as shown on the pdf document. This is to remove the MCK from CS8412 / DIR9001.
2. Solder a jumper wire onthe via hole as shown. This is connected to pin 6 of SM5842 XTI – Master Clock Input.
3. Locate a ground connection on the pcb top (can scratch out the green solder mask near the via hole).
4. Solder the coxial cable for the master clock input (+ve to jumper and shield to ground). 3.3 ~5V TTL logic or CMOS clock source should be working fine.
5. The clock source of the SPDIF input (eg CD player or Media player) and the master clock to the SM5842 must be in sync in order for the DAC to work properly.