Player and MIDI interface compatibility

Hi all, looking for anyone that might have encountered this already since I'd think it's a fairly common thing for live musicians to do but I haven't been able to find any info on it online yet.

I'm trying to set up a KPP for live use where program changes are sent via MIDI from a UTrack24 to switch rigs in time with the click tracks. The UTrack24 has a single 5-pin MIDI out to do this so according to the KPP manual you need to send this into a MIDI interface which can convert it to USB and can then connect to the USB-A port on the KPP.

Sounds simple but I'm getting different results depending on which interface I use and I can't understand why. I have a M-Audio midisport 2x2 which when connected causes the KPP to behave weirdly. If I switch rigs, there is a 10-15 second delay before it switches and only the coloured dot above the rig button changes, the white light on the button stays where it was even though the sound has changed. This happens regardless of whether the command is sent via the MIDI interface or if I just press one of the rig buttons on the KPP myself. I can also rule out it being anything to do with the MIDI command itself since it starts behaving like this as soon as the interface is connected, even if the interface isn't connected to the UTrack24. As soon as I unplug the interface from the USB-A port, the KPP returns back to normal. However, if I leave the interface plugged in, it will stop responding to rig changes (or any other parameter change via any knob or button) entirely after around two minutes. The sound is not affected during any part of this, it will just be stuck on whatever the last rig was before it froze.

I also have a Dtronics interface so I tried it with this one instead and found that the KPP freezes up straight away and won't even do delayed switching for a while like it could with the midisport. With both units, if I power the KPP on while the interface is already connected, it reaches the final light on the start up progress bar which then just flashes forever or until the interface is unplugged, at which point it finishes starting up and goes back to normal.

I've ordered an Otraki USB to MIDI cable because I've seen people using it on here with some success so I'm hopeful that will solve the issue once it arrives, but does anyone know why this would be happening? Ideally I'd want to run a MIDI cable across long stages so an interface with a built in cable is less than ideal as I'd have to start using adapters to get enough length out of it. Surely the Otraki is no different to any interface plus midi cable anyway?

If there's anyone out there that has used a stand-alone MIDI interface (without a built-in cable) this way please let me know because I will buy it immediately!

UPDATE: The Otraki arrived and I can confirm it works as expected so that will do as a solution for now. It's just slightly annoying that it's got a superfluous (for my purposes) MIDI out cable which is just going to hang loose and occasionally get plugged in by mistake by a tech, plus it's nowhere near long enough to stretch from the drum riser (where the Utrack24 is) to the rack at side of stage which has the KPP inside so it's going to need an additional MIDI cable and adapter.

Quote from slateboy

the otraki should do the job (tried and tested)

Maybe your other device is drawing too much current?

What are its specs?

Neither of the interfaces specify how much power they draw in any of their documentation, just that they are "bus powered", but I have the same thinking as you that this is in some way or another the cause of the issue.

I'm currently looking at this as a better solution since it receives power from a separate micro USB port: https://www.hobbytronics.co.uk/product/usb-midi-converter

The PSU in the rack happens to have a USB port so I've already got the means to power it. If the Otraki is the only thing anybody has successfully used maybe I'll just have to take a punt on it and see what happens.