If the VOIP refuses to turn off.
Right click on the "speaker" icon at the bottom right of Windows.
Click "Recording Devices"
Right click on a device that isn't used.
"Set as Default Communications Device"
What that will do is tell the game to use that device as the microphone (assuming it isn't an active microphone itself)
If no other devices show up you can default .. you could add a virtual device.
http://vb-audio.pagesperso-orange.fr/Cable/index.htm
If you use other programs (Skype, TS, Vent, etc). Go to that programs settings and manually set it to use the right microphone, leaving it at auto will likely try to default to the same Default Device you set above.
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You could just mute it too.
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Maybe try setting a Push-to-Talk key you wouldn't hit normally.
