Using OP-Z to clock and start 1010 Blackbox

Hi all, I have a live set coming up and I’m trying to use the OP-Z to clock and send transport to the Blackbox for longer samples. I’ve got it working great the other way around, but that messes up the bpm of my songs. I’ve obviously set up midi and clock to go out of the OP-Z. I’ve also successfully clocked and started the Blackbox using other (Elektron) devices. Does anyone have any advice who has been able to use the OP-Z in this way to lead other devices? I’m guessing I shouldn’t need to change the json file, that the app should be enough but maybe I’m wrong. Thanks.

Here is a good description, how to set the midi out: OP-Z guide: midi

How do you connect your devices? Do you use a USB hub?

I’ve read that thanks. I’m using a basic midi to usb cable which works well in many situations, and works perfectly to start the OP-Z from time he Blackbox but not the other way around for some reason. Seems like a quirk.