USB Microphone Buzzing – Possible Causes And Solutions


Modern USB microphones have made leaps forward in terms of audio quality, reliability, and versatility. These microphones are very commonly used for streaming, recording, gaming, video conferencing, and more. However, there is a common problem with USB microphones: they buzz. What could cause a USB microphone to buzz, and how do you fix it?

USB microphones can pick up buzz from surrounding hardware; they can buzz due to too much gain in the mic signal, when the incorrect hardware for the mic is being used, or the mic is damaged. The most common solutions to reduce buzz are to lower the gain settings, use a USB hub, repair the mic, and shield it from humming hardware.

USB microphones are very useful, but when they develop a buzz, it can be very frustrating. This buzz is often caused by something simple that can be solved quickly, but sometimes the problem is more serious. Let’s look at what may cause a USB microphone to buzz and how to resolve the issue.

Possible Causes Of A buzzing USB Microphone

There are a few possible causes of an audible buzzing heard from USB microphones, and some of them are very simple to solve. A buzzing microphone can be very frustrating while you are trying to stream or record, and fixing it is imperative.

Below are some examples of the possible causes of a buzzing USB microphone:

1) Excessive Gain

Gain is a very misunderstood aspect of microphone use, and there are few who use USB microphones that fully understand it and how important the proper use of gain is for clear audio quality.

Gain is the amount of drive or power that is used to amplify an audio signal. Every audio signal must be amplified in some way to be audible, and increasing the gain increases the amount of power used to drive the signal.

Many believe that increasing the gain settings for a microphone signal will simply increase the volume of the microphone output.

While increasing the gain does increase the mic volume output, it also increases the noise that is output by the microphone audio signal.

This is because increasing the gain does not simply increase volume, but it increases the strength of the signal, which makes it more sensitive and prone to distortion and buzzing.

The gain levels or setting being too high is a very common problem that causes significant buzzing in USB microphones, especially while the microphone is in use.

2) Hum From Computer Hardware

Some USB microphones are surprisingly sensitive. They are able to pick up sounds and noises from surrounding electronic hardware very easily.

USB microphones are used in very close proximity to computers, and computers are noisy machines. The whirring and buzzing of computer hardware is very commonly the cause of buzzing that is heard in a USB microphone.

Another source of hum from computer hardware is improper grounding. Most laptops are not electrically grounded, and the same is true for many computer power supplies, which means that if the electricity source where you are is not groundedand excessive electrical hum will be produced when a microphone is plugged into the computer.

Whether the mic is picking up a physical hum or there is an electrical hum due to poor electrical grounding, hardware noise is a common source of USB mic buzz.

3) Problems With Native USB Input

The native USB inputs on most computers are not sufficiently powered to run a microphone correctly.

Microphones often require specific power sources and regulation, especially condenser mics, which normal USB ports are not usually equipped to handle.

Not powering your USB mic correctly can be a source of significant hum or buzz when using the microphone.

If you are using an unpowered USB hub with multiple outputs this might have the sufficient power for your USB microphone. 

4) A Damaged Microphone

A very obvious cause of mic buzz that is often overlooked is damage to the hardware.

Microphones are sensitive pieces of equipment and can be damaged more easily than most people realize.

A damaged microphone may be malfunctioning, which may be causing the buzz that you hear when using the mic.

If the diaphragm in the mic is not functioning well or not responding quickly enough to the audio source, the mic will hum as a result.

5) A Damaged Microphone Cable

A damaged mic cable is a common cause for mic buzz as well. The cable for the microphone, whether the power cable or the audio output cable, is integral to the proper working of the microphone.

If the power cable is damaged, the mic may be receiving intermittent power, which can damage the mic or cause a buzzing in the audio signal.

If the audio output cable is not working properly, there may be buzzes generated within the cable and not in the microphone itself.

Possible Solutions For A Buzzing USB Microphone

The problems that are listed above are not the only causes for buzzing in a USB microphone, but they are the most commonly experienced issues.

Fortunately, all of these problems have solutions.

Here are ways to solve the issues that cause a buzzing USB mic:

1) Reduce Gain Settings

Reducing the gain level for the microphone will undoubtedly reduce the buzzing noise that you are hearing.

Whether the buzz is caused by the gain level itself or the high gain level has increased the sensitivity of the microphone to allow it to pick up outside hum, reducing the gain level will solve this issue.

Reduce the gain in the recording software that you are using or in the hardware settings on your computer, using the driver software for the microphone. If you are using a DAW such as garageband, check the input meter isn’t peaking in the ‘red’ as shown below as this will cause the signal to distort. Turn the input down and record at a lower level, you can always turn up the recording later. 

2) Sheild Microphone From Hardware Hum

Shielding the microphone from the hum or hardware can be as simple as placing some simulation phone under your microphone stand to absorb vibrations or moving your hardware further away from your microphone.

If the hum is generated from a lack of electrical grounding, you can ground your computer by simply touching it or by taping some copper wire (found easily at any hardware store) to a metal surface on the computer and a metal surface that touches the ground.

This should remove any buzz that is generated from poor electrical insulation.

3) Use A Powered USB Hub

The native USB inputs on most computers are not sufficient for properly powering some USB microphones.

To solve this issue, use a powered USB hub. A powered hub will regulate the energy sent to the microphone and supply sufficient power to properly run the equipment.

Be sure that the power rating on the USB hub corresponds with the power rating of your USB mic to avoid damaging the microphone.

4) Check For Damage To Microphone

If the microphone has been somehow damaged, it may cause a buzz in the audio signal.

If you are feeling brave and you’ve tried all the other methods then you can try carefully open the microphone to check if either of the wires that are connected to the internal diaphragm has come loose. If so, reconnect the wires, and the buzz should be resolved.

This is only recommended if you have experience in fixing electrical equipment and if the microphone is still in warranty it’s probably better just to send back to the manufacturer for repair or replacement. 

5) Check For Damage To Cable

Damage to the cable of the microphone may cause an intermittent power supply to the mic, causing the microphone to malfunction.

Check for any signs of external damage that may have been caused by mishandling or wear and tear. If there are any damage to the cable or the cable shielding, the cable may need to be replaced.

If the Microphone simply runs from one USB cable, replace the cable. If there is a separate USB and power cable, check each cable and replace one or both of them if you suspect any damage.

For some USB microphones, where the cable is removable, this is simpler than for others where the cable is not. For the latter you may simply have to buy a new microphone or send it back to the manufacturer to be fixed. 

Conclusion

USB microphones can be delicate, and there are many issues that may cause unwanted buzz or hum in the audio signal.

These problems are usually simple to rectify, but you need to know where to look to isolate the issue before trying to resolve it.

Always carefully examine the microphone for any damage before taking further action.

If there is no obvious damage to any part of the microphone, then check the software that you are using for the microphone, and check the gain settings for the mic.

If the problem persists, try to insolate the microphone from grounding issues or hardware hum.

If none of these solutions solve the buzzing, take the microphone to a qualified technician to help resolve the issue.

A microphone tech should be able to easily and quickly identify the problem and guide you on how to solve it.

If your mics are buzzing, there is something that can be done about it! Take your time, find the root cause of the issue, and find a way to fix it before considering a replacement mic!

Rob Wreglesworth

Rob has come to terms with the fact he will probably never be a famous rock star....but that hasn't stopped him from writing and recording music in his home studio. Rob has over 15 years experience of recording music at home.

Recent Posts