I'm a little bit of a "layman" in this area.
Normally I work mostly with VST-plugins in Cubase + synths and effects from Scope, so there's no timing issues and works just like it should work and I said long time ago I have enough of software and it's enough to work just with Scope

But,
I have Korg Minilogue XD desktop synth.
I have purchased external box which "converts analog trigger-clock-signals to MIDI-clock-signals and vice versa." for syncing synth with Cubase.
When I connect Midi-out from Luna II to Midi-in's Clock box and then clock-sync out to synth's sync-in and start Cubase,
synth is "swinging" in timing a lot, there's no perfect sync at all.
I have tried different settings in Cubase (external synchronization" and it's always the same.
On synth (Korg) I can see that synth's clock is "external", so it's connected to clock-box.
Sync box setup is correctly , from provider :
1. setup cubase to be midi-master (?)
2. connect the midi-out of your computer to the midi-in of an
audiowerkstatt trigger2midi2trigger.
3. connect the analog clock-output of the trigger2midi2trigger to the
sync-input of your synth.
4. setup the audiowerkstatt trigger2midi2trigger this was:
a) input: midi
b) trigger-type-out: v-trig
c) clock-divider-out: 1/8
d) pulse-length: middle"
"setup cubase to be midi-master (?)" - how to check for this.
When I connect synth directly to computer, via USB or Midi connection, synth plays fine, but I thought i'm gonna have even better results with external sync box.
Any tips or recommendations maybe, probably question more for Cubase users or ?
Also question ,
If synth has USB out/in option for connection (for editing pathes also directly on computer's editors) or is better just to use Midi connection, so there's less USB connections on computer for better computer system stability ?