If you have old USB headphones you can easily transform them to a USB sound. This card can be helpful during testing of home built devices connected to the speaker or microphone ports on the PC (for example A proof of concept of a simple sonar and Constructing a homemade microphone).
I used broken Audio 655 DSP headphones with working electronic inside. They have below features:
- Powered from USB.
- Stereo output.
- Built-in microphone.
- Mute/unmute switch.
- Volume up/down switches.
- Power on LED indicator.