You can find the step-by-step tutorial on how to set up the FIFINE K780A from the video below.
Self Troubleshoot before proceed any further.
Please include the test result when resorting for email support.
1.Is "USB PnP Audio Device" seen by your Windows or Mac or is recognized as unknown device?
2.If it's recognized, is what you want to hear mic playthrough you computer speaker? (Enabling system monitoring feature on Windows or using Quicktime Player on Mac).
3.If computer sees it as unknown device, have you test out on a different computer? Tried to update and reinstall the unknown driver for a few times on the same computer?
Q: It didn't work even after reinstallation and update of the microphone driver.
A: Please try clean up the USB registry of your PC. Download the application through the link below. The code for unzipping the file is fifine
First Plug the K780A into your computer, uninstall the "Unknown USB Device" under the Device Manager, then unplug the microphone. Skip to the second step if there's no "Unknown USB Device".
Next, stay on the Device Manager, double click the app to run. Select “Clean”.
Finally, restart the computer and replug the mic to another USB port.