Finding an "official" M-Audio Radium 49 driver for modern macOS versions (like Monterey, Ventura, or Sonoma) is technically impossible because they don't exist. However, because the Radium 49 was designed during a transitional era of MIDI technology, you aren't completely out of luck. The Problem: Legacy Architecture

To understand why the Radium 49 is difficult to use on a modern Mac, we have to look at how technology has shifted.

Plug the "MIDI IN" cable of the interface into the "MIDI OUT" port on the back of the Radium 49.

The last official drivers were for macOS Mountain Lion (10.8). Summary Checklist for Success Recommendation Official Driver Discontinued Do not rely on finding a modern driver. USB Connection Unreliable Likely to fail on macOS 11+. 5-Pin MIDI Output Highly Reliable Use a USB-MIDI interface cable. Power Supply Use a 9V DC adapter.

Ensure the "Radium 49" or "USB MIDI Device" is enabled for Input. Troubleshooting: What to Do If It Doesn’t Work

port to your Mac. This bypasses the need for legacy Radium drivers, as most modern MIDI-to-USB interfaces are "class-compliant" and work automatically. Legacy Drivers (Old Systems Only)

Disclaimer: The author is not affiliated with M-Audio or the developers of the midisport-macos project. The use of third-party drivers involves inherent risks, and readers are advised to proceed with caution and only use software from reputable sources.

Once you've downloaded the driver, follow these steps to install it:

: macOS dropped all support for 32-bit software and drivers. Apple Silicon Macs cannot run the kernel extensions required by the ancient M-Audio installer.

: Plug a 5-pin MIDI cable into the MIDI OUT port of the Radium 49.