Mbox Studio USB high pitch noise

[Serial Butcher]

Hi all,

New to this wonderfull forum full of information.

I recently purchased an MBox studio with latest version of PT and Mac mini M4 sequoia
But can't seem to find info about my issue, a high pitched noise and i think it is coming from the usb output of the Mbox Studio.

I have nothing connected to the Mbox inputs, only main outputs 1&2 (unbalanced) go to my amplifier (unbalanced) and speakers connected

I pulled out the usb cable that is connected to the mac mini,the high pitch stays, when i unplug the usb cable from the Mbox Studio, it is gone.
Anyone have this same issue?

I don't see noise on the meters of the mbox.

cheers!

[spacepluk]

It sounds like the typical USB ground loop. Try balanced cables, connecting everything to the same powerstrip, etc.

[Serial Butcher]

This is what i was starting to think too.
I will try with some powerd speakers that i can get from a friend and connecting with balanced cables.



Just tested with headphones and then there is no noise.


i have uploaded a small .WAV file so you can hear it.
https://we.tl/t-OeIRgL5LXP


You will hear a click of when i plug in the usb in the Mbox(nothing on the other end), and then the high pitch appears.
When i unplug you hear another click of unplugin the usb and the high pitch is gone
The hiss is you hear is normall because the power amp is full open.

[spacepluk]

Yeah, that's definitely it :)

[Serial Butcher]

Ok, i checked some more and it was also in the headphones, forgot you have to route everything manualy in the control app to the headphones.



Butt have tested with active speakers and balanced cables and the high pitch is gone.


Also tested back again with my unbalanced amp and passive speakers and put in between the MBox a Palmer line isolator, unbalanced to balanced and with this the high pitch is also gone.
So balanced connection is the solution.


Now i encountered another problem.
A kind of static crackle/click when you turn the jog wheel of the main volume
It is like every little turn on the wheel transfers to the tweeters.


I also recorded a little sound file of this
https://we.tl/t-OXbwcfriWC


guitar straight into instrument input, and strum the guitar, and then turn the main volume up and down and hear this static with every turn.
You also hear this when just playing calm music, turn volume up or down and hear this noise


This you can not hear in the headphones.

[Serial Butcher]

Using balanced connections and the high pitch noise is gone.


Problem solved.


but also encountered another problem, will make a new topic about that.

[SixChurchStreet]

Thanks for this topic. I'm having a similar issue. That sound was driving me nuts. Will try some different cabling.

[SixChurchStreet]

Checked to make sure I used nothing but balanced cables and I think my high pitched whine is gone. Thanks everyone.

[eluciii]

1. Check Your Connections
Ensure your USB cable is securely connected and try using a different USB port.
If possible, test with a different USB cable to rule out cable issues.
Avoid using a USB hub—connect the MBox Studio directly to your computer.
2. Power & Grounding Issues
If using a laptop, try running on battery power (unplug the charger) to check if the noise is related to ground loops.
Plug your computer and MBox Studio into the same power outlet to minimize potential grounding issues.
3. Driver & Firmware Updates
Ensure you have the latest drivers and firmware updates installed for the MBox Studio. You can download them from the Avid website.
4. Buffer Size & Sample Rate
Try changing the buffer size and sample rate in Pro Tools or your system’s audio settings.
Mismatched sample rates can sometimes cause digital artifacts or high-pitched noise.
5. Disable Unnecessary Audio Devices
On Windows, go to Sound Settings > Playback Devices and disable any unused audio devices.
On Mac, check Audio MIDI Setup for conflicting settings.
6. Test on Another Computer
If possible, try connecting your MBox Studio to a different computer to see if the issue persists.
7. Forum Post Format (If Needed)
If you need to post this issue on the Avid Audio Forums, use a format like this:

Issue: High-pitched noise from MBox Studio USB
System Details:

Computer: [Your computer model]
OS Version: [Your OS version]
Pro Tools Version: [Your Pro Tools version]
Audio Interface: Avid MBox Studio USB
Troubleshooting Steps Taken:[List what you've tried]
This helps forum members and Avid support provide better assistance. Let me know if you need more details! 🚀