Shabs22

Pretty sure this has to do with the fact that the Korg is sending clock to the Del, while the Del is also sending to the Korg, i.e. a midi loop. Try going into the settings menu and turning midi clock IN off on the D, and see if that mitigates the problem. You can also try using the Korg's editor to make it not send midi clock/ make it run on external clock.
Let me know if it doesn't help

First of all, thank you Icoustik, for your fast response (and also for them amazing multi-samples you've uploaded)!

I've looked into it, double checked the MIDI-settings on the Deluge, then tried looking into the settings of the Korg and found out that the driver was out of date (last one they put up was in 2019 - for Mac OS 10.10 to 10.14).
I've got a Mac, with OS Catalina 10.15.x, so unable to install a driver where I could have possibly changed the "not send midi clock/ make it run on external clock" - settings.

I'm returning the Korg and will swap it for another MIDI-keyboard, hopefully I'll have more luck.
Will post if it works.

Thanks again for your help

@Too_Mere said:
Not currently possible, sorry.
Reverse is set for all notes of the synth instrument or kit row.
You could have the reversed sample on Osc 2 and modulate volumes for single notes though.

Alright, will have a fiddle with that. Thank you