Maybe a touch of flat black paint or felt pen might help?
Yes a black sharpie has worked well for me in the past. It will dim it in increments as you put in on in layers.
So I’m unable to get the Matrix to work for me with Mac or Lumin. I have the 9v iFi iPower X plugged into it and the LED up front is not on. I see red lights inside the Optical input so I know its getting power. Am I supposed to turn on any of the DIP switches on the bottom of the Matrix? Or did I just get a bad unit?
So I just discovered something interesting trying to get the Matrix to work with my MacBook Pro. Although the Audio MIDI does not see the Matrix as an output device, if I go into System Information and check the USB, it shows up as “X-SPDIF-2” being connected to the USB. The computer is not recognizing the Matrix as an audio output device. I have a message into Matrix to see if there is a driver that I need to install. Will let you know when I hear back.
There are no drivers needed for Mac OS only Windows.
If the front light is not lit up according to the manual it means that the Matrix is not seeing the USB from the output device. Since it is two different devices you might want to try a simple certified cable like from a printer or at least another cable. If there was a cheap cable in the Lumin box try it.
My assumption was if powered on by external power and it lit Green. Either way I do get a Green light when I plug in a USB. I’ve used the USB that came with the Matrix, a Nordost, and a Curious and neither change the issue. I see the Green light in I2S on the DSD but no Audio. I’ve emailed Moon Audio who I got the unit from hoping they can replace it or give me my money back.