I can't be heard when using Google voice/Google Hangouts.

I've always been a fan of Google voice, and I have used it for a long time. In the past, I would periodically try to make calls using Google voice and the person on the other end would not be able to hear me.

Now, this problem has persisted for a handful of months. Here is what I have tried:
deleting the plug-in and reinstalling.
Reinstalling Google Hangouts.
Making sure the playback device is set to the device I am trying to use.
I always use Google Chrome when trying to make calls.

I have a phone interview coming up on Monday. And Google voice works a lot better for me than my cell phone or a landline. So, I'd like to figure this out.
Any advice would be greatly appreciated.