I’ve had my Innuos Zen Mk3/MHDT Orchid DAC setup in my system for 30 days or so and I’m very satisfied with this combo. The Zen is USB only. Just noticed today that I’m getting a slight hum from the DAC and it goes away when unplugged. No hum through my speakers when connected just the DAC. Any help with eliminating the hum is appreciated.


It’s a shame that DACs still don’t have galvanic isolation. Meaning, there is often metal to metal through which can cause both analog and digital effects. It’s rare to see this from a streamer though, the usual culprits are PCs.

In your case you have an analog one and the fix is cheap, you need a USB isolator, though not all DACs work with them.  Usually, they don't need to be powered, but in some rare cases the DAC won't recognize the input unless there's a DC voltage so you may need to get a separate supply:



Some DACs do have galvanic isolation but they are at the higher end of the scale. One company is making DAC’s from Panzerholz  and other wood with inertial filters. I also use a USB isolator by Wyred 4 Sound. Just for extra protection. https://www.lessloss.com/echos-end-p-218.html

A DAC is not a streamer. A few DACs have built-in streamers - not this one.

What is a "slight" hum?

Does it show up in the analog downstream during a listening session? Is it a recent phenomenon?

Hum is a grounding issue.