Cannot claim USB device on High Sierra

[Sean Luke]

I am very new to USB so forgive me if I ask something which is in the FAQ.

I am trying to build a Java software tool to communicate over USB with the Korg MicroSampler, a kind of synthesizer keyboard from 2008 whose existing closed-source tools are being obsoleted with recent operating system upgrades.   I am on MacOS X High Sierra.

When I attempt to claim the MicroSampler USB device using 1.3.0, I get an "Unknown Error (-99)".  If I use an earlier version of USB4Java, I get an "Access Denied (insufficient permissions)".

I have absolutely no idea why this is the case.  I would presume it's due to permissions locking as part of Apple's campaign to make life harder and harder for software developers.  It's possible that Korg has some custom USB thing, but I do not believe this to be so.

I'm wondering if anyone has an explanation for errors of this type, and how I can work around them without asking my users to disable major security features in their firmware (they're musicians, not software developers).  Is this the new normal?  Should I give up on attempting to do Java USB on the Mac?  :-(

Sean Luke