Beat sync korg volca beats and rekordbox ddj 400

I think there is a possibility:

• Use rekordbox 6 (performance mode). The biggest improvement of Rekordbox 6 is the implementation of Ableton Link (in my humble opinion).
• Enable Ableton Link in Rekordbox
• Use another tool to convert from Ableton Link to midi, for example Ableton Live (https://help.ableton.com/hc/en-us/articles/209071149-Synchronizing-Live-via-MIDI)
• Connect the Korg Volca Beats to your computer via a midi-to-usb cable 

Thank you very much for your quick answer!

Indeed it's working. 

The only thing, I cannot find a way to control the bpm of ableton via ddj 400... Other way around it's working.

You're welcome. Regarding being unable to change the bpm of ableton via your controller: this is a known shortcoming of the current implementation. You can find some details here: https://forums.pioneerdj.com/hc/en-us/community/posts/360061730411-Make-Ableton-Link-bidirectional

There is a work-around: you can type in the bmp value via the Link popup window within Rekordbox 6 (but that is still outside  your controller).

Such a pity!

With Traktor it's possible without an Ableton Link.

I hope Pioneer Dj will fix this soon!