I'm using a USB device that combines a few inputs(optical, USB, 3.5mm) and outputs them to one 3.5mm port. After outputting my MacBook Pro sound to the device through USB for a few minutes there appears noise and not long later it becomes so unbearable that I have to pause the media. That cycles every 3-5 minutes provided that I output it through USB. If I output through the 3.5mm jack, however, everything is smooth. I tried using the device on a Windows computer and outputting through USB worked fine. I also recorded the outputted audio(screenFlow) and there was no noise there.
Sounds like a problem with the audio format. Open the Audio MIDI Setup application, select your USB device, and try different combinations for audio format (sampling rate, channel/bit-depth).
If your device is locked at a sample rate and/or bit-depth, this should be a workaround. Try creating a Multi-Output Device with your device and the Built-in Output. (note: with the multi-output, you will have to set the volume on each device individually)
- Click the + icon at the bottom left and select Create Multi-Output Device.
- Under the "use" column, select Built-in Output and your device.
- Set the Master Device to Built-in Output. This will allow you to choose different sample rates based on what is allowed for Built-in Output.
- Lower the volume on Built-in Output (essentially muting it so sound only goes through your device)
- Right-click on your device under the Multi-Output Device and check Resample this subdevice.
- In System Preferences > Sound, change the output device to the Multi-Output Device.
Now you can change the sample rate of the multi-output device.