How to fix microphone noise on a computer

2025-04-15


I'm experiencing significant noise from my microphone after connecting it to my computer. Sounds like the CPU fan, hard drive, and optical drive are all being picked up. How can I fix this?

Q: I'm experiencing significant noise from my microphone after connecting it to my computer, including sounds from the CPU fan, hard drive, and optical drive. How can I resolve this issue?

A: Here are some solutions: (1) If the noise is indeed from the hard drive, optical drive, and CPU fan, it might be due to poor filtering circuitry on the motherboard or power supply, failing to filter out interference from these components. Shortening the IDE cable and CPU fan power cord can reduce the impact of these devices. You could also try replacing the power supply. (2) If unshielded cables or poorly grounded shielded cables are used to connect the microphone to the sound card, external high-frequency interference signals entering through the microphone can cause noise. In this case, the noise should disappear after unplugging the microphone. If the issue is caused by the microphone connection, replace unshielded cables with shielded ones. If shielded cables are already in use, use a multimeter to check if the outer metal shielding layer is connected to the chassis to rule out poor grounding. Additionally, the signal cable from the sound card to the powered speakers should also be a shielded cable and grounded. (3) In the 'Start' menu, open the 'Paint' program in 'Accessories' and open a high-color graphic. Cut out a section and quickly drag it with the mouse. If you hear a 'swishing' sound during dragging, it's due to high-frequency radiation from the motherboard or graphics card. Try moving the sound card to an expansion slot farther from the graphics card, and use an aluminum shield to shield the sound card and ground it to reduce the impact of high-frequency radiation. (4) Check the connections between the speakers and the sound card. Do not reverse the Line Out and SPK connections. The Line Out jack outputs an unamplified audio signal (high impedance), used for connecting powered speakers or amplifiers. The SPK jack outputs an amplified audio signal (low impedance) from the sound card's built-in amplifier, used for connecting passive speakers or loudspeakers. Incorrectly connecting the input of powered speakers to the SPK jack can cause noise due to impedance mismatch and distortion from double amplification of the audio signal (including noise). (5) Replace the sound card with a higher-quality one.

Related Blog