I can hear people, but they can't hear me - apparently my microphone isn't working (and no, it's not set to 'mute')

Plug the USB connector into another available USB port.
• Check your computer's volume level.
• Check if your computer's volume is muted.
• Check your operating system's audio input and output settings.
• Check the headset's volume and mute settings.
• Restart computer.

If these don't resolve your issue, I would recommend pursuing replacement options.

Try with another headset.

Try to reinstall the Driver.
http://support.lenovo.com/en_US/research/hints-or-tips/detail.page?DocID=HT072728

Check the Volume settings.

Go into sound properties and make sure the microphone properties isn't checkd at "mute".

Please use an external handsfree headphone set and if the voice is clear then the microphone in the phone is a suspect. Please CLEAN the port of the mic on the panel to remvove any obstruction or dirt accumulation.
If this wont help then the microphone must be replaced.

Here are a couple of things you can try. I included the link for the user guide below.

Callers cannot hear me.
• Headset is muted. Press the mute button on headset to unmute the microphone.
• Headset microphone boom aligned incorrectly. Align the headset boom with your mouth.
• The USB adapter is not set as the default Voice device. Use the Voice settings in Windows under Sounds and Voice Devices to select "Plantronics C610/C620" as the voice device.

Here is a link to the Plantronics C610 User's Guide.

Good luck from Headsets Direct!

Double check that you are all in the same party. If you are not in the party and they are you will sound very quiet to them. It almost sounds like you are in the background. So go and make sure you can join the party. If that does not solve it go into your settings and double check that mic volumes and everything are all up.

Make sure that the phone isn't muted. There should be a button that looks like a microphone. If it's gray then the phone is muted. If it isn't, try using the camera or something to make sure your phone's microphone isn't broken.

Your phone is either muted on your end or the microphone has gone out on it. Next time you're in a call look in your call options and see if there is a mute option, or see if there is a microphone symbol with a line through it on your call screen. If there is a microphone symbol with a line through it click it to turn the mute off. If you don't have a mute option on your phone then chances are the microphone has gone bad.

Go under the volume control in Windows and make sure that Windows is using the camera as the recording/input device and make sure the volume isn't set too low or muted.

one of 2 things:

1. your microphone is set to MUTE and you don't know it (could be either a Profile setting or an explicit MUTE setting)

2. your microphone is BROKEN

You need to specify what type of phone it is, and what you did before it stopped working.

Good luck!