Sometimes, in their infinite wisdom, both Windows and macOS can suspend operation or only allow low power from USB ports. Your DAC may be plugged into a low-power USB port.

Note: this section can also apply to headphones that connect directly to your PC via USB, if you’re having similar troubles. What to do if your DAC keeps disconnecting or is not recognized If you’re using an SACD player as your digital source, be aware that Sony owns the SACD format and mandated that the digital output from an SACD transport must be encrypted (as well as the audio on the disc itself).Try connecting a different digital source if you have one.For the purpose of troubleshooting, if you don’t have another 75Ω coaxial cable, you can substitute a regular RCA (phono) interconnect cable. Try a different optical or coaxial cable.If your DAC has multiple inputs, check that it is switched to receive the correct one.A simple way to check if an optical digital output is active is to look for the red light coming out of it. Confirm you’ve connected the digital output from your source and that it is functional.Sometimes restarting the playback application is necessary. If you’re using a computer as your source, make sure you’ve selected the DAC as a USB output device or selected the computer’s S/PDIF output (depending on how you have it connected) in both the Control Panel (System Preferences) and in your audio playback software.Here’s what to check for and what you should try to fix the problem. You’ve connected your digital source to your DAC, and your DAC to an analog output device such as a headphone amplifier and some headphones, or an amp and some speakers, but you’re not hearing anything. What to do if there’s no output from your DAC Before you reach for your credit card (or a hammer), here are some ways you might be able to fix your Digital to Analog Converter (DAC) first. And like many things in life, adding computers to the mix can complicate issues. Glitches, clicks, crackles, and pops, or no sound at all-digital audio can have its moments.

Usb to digital optical converter