DVS Setup Guide (in English) is here.
https://rekordbox.com/_app/files/img/rekordbox_dvs_Setup_Guide_en.pdf
Would you check some point ?
・Did you install driver of DJM-900NXS2?
https://www.pioneerdj.com/en-us/support/software/djm-900nxs2/#drivers
・Did you activate DVS? (Preference -> License -> rekordboxDVS)

・Would you check your AudioDevice? (Preference -> Audio -> Audio)

・Would you check "Enable DVS Function" ? (Preference -> DVS)

・Would you check Timecode Setting? (Preference -> DVS -> RoutingSetting -> ControlHardware)
