How do I resolve MIDI input issues and ghost images on macOS Sequia 15.0.1 with a powered USB hub?

Question

How do I resolve MIDI input issues and ghost images on macOS Sequia 15.0.1 with a powered USB hub?

Using Sequia 15.0.1 on mac mini. I need to be able to use a music program that requires input from keyboards. Program itself runs, but will not recognize midi input from keyboard. midi monitor does not show input from system,

but checking midi monitor with a different computer shows it is working. USB in from wired computer keyboard and mouse do work. Another issue is that when closing programs, a ghost image of the program remains on screen. I am using a powered USB hub to connect all systems to the computer.

Thanks

Thom.

[Re-Titled by Moderator]

Original Title: sequia USB question

Earlier Mac models

Posted on Dec 25, 2025 3:52 PM

Reply

Answer 1

Dec 25, 2025 10:16 PM in response to thomas fromchicago

Unless it’s a secret, it would be helpful to know exactly which application(s) you are having trouble with. Someone here may know how to assist if you provide specifics.

Also, just which year Mac mini is this that is running Sequoia?

Reply

Answer 2

Dec 26, 2025 3:12 AM in response to thomas fromchicago

In addition to what D.I. Johnson said: recent versions of macOS have increased restrictions on connecting peripherals, you usually have to grant permission before a usb device can connect.

Does the midi keyboard show up in System Information? - Hold down the Option key and from the Apple menu choose System Information, then click on USB. Does the keyboard appear there or not?

If it does not, then maybe it's blocked by the security settings.

If it does appear there, it should work, at least, with Apple's GarageBand. Please test.

Also: you may want to test connecting the keyboard directly. You probably need one simple passive adapter from USB-C to USB-A, like this: