USB Microphones can be EQ'd depending on which recording software you're using, but usually after recording. However if it was working well previously, and isn't working currently, then we will need to troubleshoot, and maybe even recommend Service. Unfortunately, there is no hard-reset for the microphone, other than unplugging it and rebooting your computer.
To be absolutely certain, please make sure you are addressing the AT2020USB from the side where the blue light is, as this is a side address microphone and should not be addressed from the top or back. Other than that, you may also try a different USB cable and computer. If that does not resolve your issue, then Service with ATUS will be recommended.
If you are not located in the United States, please contact the division for your world area. http://www.audio-technica.com/world...
If you are located in the United States, then please visit www.audio-technica.com/service
for information on how to obtain Service with ATUS.