How to improve sound quality

Hi everyone

I have a condenser microphone (Zingyou BM-800) running through a Neewer 1-channel 48V phantom power unit. I am using XLR to XLR from mic to power supply, then XLR to mini-jack to the PC. I am unsure if the cable is shielded (either from the mic to power supply or from power supply to computer).

I have the microphone set up within Windows 10 at 100% with a full gain of 30dB. When speaking to others online this is fine but when I record in Microsoft's own voice recorder software I get a distinct set of clicks (electrical data from the PC?), as well as the slight hum from the PC itself.

I know I need to replace the fans in the PC (they're a little old anyway) but how do I resolve the clicking sounds? I am assuming that having the mic at 30dB gain with 100% input signal is not good?

Would appreciate any and all advice. 😁