USB has come a long way—with Mac, Windows, Android, and iOS, most things should be pretty much "plug and play." Well, sometimes only with the right dongles. But you get what we mean.

No Output from the DAC

1. Make sure you’ve selected the DAC in BOTH System Preferences/Control Panel and your player software (Bitperfect, Amarra, Audirvana, Foobar, JRiver, etc…) Sometimes you’ll have to restart the player again, too.

2. Remember that a DAC with multiple inputs has to be set to the USB input. Believe it or not, some people miss the button on the front panel.

3. If the above doesn’t work, try a different USB cable or USB port. Yes. There are a ton of dead/crap cables out there. And dead USB ports. ESPECIALLY USB-C. You guys wanted it, but the reality is that USB-C cables are LESS reliable than USB-B (printer cable). Start with a different cable. Seriously.

4. If you’re still not hearing music, make sure you don’t have the volume turned all the way down on your player software.

5. Still no sound? Are you using an amp and headphones or speakers? The DAC won’t make sound by itself.

DAC Not Showing Up In Control Panel or System Preferences

If you’re using Windows:

1. Try a different USB cable, 2m or less in length, USB 2.0-rated, non-audiophile type. Seriously. See comments on USB-C above.

2. Try a different USB port. On some PCs, if you only have USB 3.0 ports, you may have to update the USB motherboard driver to ensure they are compatible with USB 2.0.

3. Try a different PC. If it works on that one, guess what? The problem is the other PC.

4. You may be having port power management problems. Try it with an externally powered USB hub.

5, If you are not using Windows 10 with a non-Unison USB™ DAC, you may need Windows drivers. These are available at schiit.com/drivers

If you're using a Mac:

1. Try a different USB cable, 2m or less in length, USB 2.0-rated, non-audiophile type. See comments on USB-C above.

2. Try a different USB port.

3. Try a different Mac or PC. If it works on that one, guess what? The problem is the other Mac.

4. You may be having port power management problems. Try it with an externally powered USB hub.

5. If you're on MacOS Ventura, please note the following oddities: (a) it will ask for permission to access your DAC. If you don't say "yes," you won't be able to use it. (b) turning the volume all the way down mutes the output from your DAC. Otherwise, volume does not work.

Distorted Sound or Drop-Outs

1. Try a different USB cable. Long USB cables can be problematic. We recommend a USB cable of 2 meters or less in length. You can use long analog cables on all our DACs if you need to span a distance between DAC and amp. And yes USB-C cables are worse. Start with a different cable.

2. Throw away that hand-made, pure-silver, lambswool-insulated USB cable. Audiophile USB cables can be problematic. Yes, we know, you spent ten billion dollars on it. Well, that’s cool and all, but in our testing, many audiophile brands are not capable of USB 2.0 transmission rates. Get a short, true USB 2.0-rated cable from Belkin (or our PYST cable, which is tested at USB 2.0 speed.)

3. Some USB ports have strange power management behavior. If you have power management options that include things like "Power Saver" mode, the USB port may not provide enough power to the DAC when the computer comes out of sleep mode.

4. Some anti-malware and anti-virus software may interact with Windows UAC2 USB audio interface and cause audible problems such as dropouts, pops, and glitches. Consider disabling such software and using the standard Windows Security options in Windows 10, including Firewall and Defender options if needed, since these are engineered specifically to work with all Windows drivers and capabilities

5. Consider a new computer. Some computers are so old they don't support USB 2.0 (yes, really), and some OSes are so old they don't work well with modern products. Windows 10/11 is best for a Windows machine, and is required for Unison USB. For Macs, you're looking at 10.7 and above for non-Unison USB DACs, and 10.10 and above for Unison USB DACs.

DAC Not Recognized/Disconnecting

1. You may have a low-power USB port. In their quest to save us from excess USB power consumption, Windows and MacOS can cause problems by selectively suspending operation and/or having only low power available from the USB port.

2. On PCs and Macs, you may be able to eliminate it by disabling port power management. See here:

https://www.windowscentral.com/how-prevent-windows-10-turning-usb-devices and https://support.apple.com/en-gb/HT204032

3. For all devices, a definitive solution is to use an externally powered USB 2.0 hub and insert it between your computer and your DAC. This provides power that an underpowered USB port cannot.