Why does the USB audio device have problems with Google Hangouts

audiogoogle-hangoutsmicrophoneusb

The audio sent to the person I'm talking to is very faint when using my USB audio headset and Google Hangouts, even if I turn the level up high in System Preferences. In Skype, everything is normal. What could be going on?

MacBook Pro (Retina, 15-inch, Mid 2014)

10.10.2

Plantronics .Audio 478 Stereo USB Headset

Chrome

update: it seems that refreshing window (essentially re-joining the hangout) causes the correct mic to be detected.

Best Answer

Make sure you've selected the Plantronics device in the mic chooser window in the Hangouts settings once the Hangout has begun (gear icon.)

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Change the default setting (which should be the internal mic on the Mac if there is one:)

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To Plantronics:

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(I have the Blue Snowball connected in this screen cap.)