Why might a condenser microphone suddenly only record very close sounds?
Welcome to the board, Joel. Let's try to do some remote troubleshooting.
It's important to recognize that the problem could originate not just in the microphone, but in the computer's USB sound driver and its settings.
Before blaming the microphone, review your computer's sound settings, in particular the microphone volume/gain setting. I can't give you exact instructions because they vary with operating system and sound drivers, but look for a microphone or input gain setting, as well as any &quot;automatic&quot; option (disable that). There's usually a built-in test function to see whether the signal coming in is of a normal level when you talk.
Also look at whatever application you're using to record the sound. Could a gain setting in that software have been changed inadvertently?
If you have access to another computer, it's worth swapping it in. If the sound remains low, then it probably is the microphone itself. (I'm not going to insult you by suggesting you make sure you're talking into the front side of the microphone.)  The condenser capsule could have been damaged if the microphone was dropped. Or the circuit could have failed from a static discharge when the USB plug was inserted. None of these are easily fixable unfortunately. Is it under warranty?