Logic Pro 11.0.1 Issue with usb mic setting bleeding into guitar tracks and creating a crazy echo

Hope I didn't scream too loud. I finally decide to go big and move up from Garageband, which I love, to using Logic. I record a couple of guitar tracks, a bass track and a drum loop. All good.

Then I wanna throw a scratch vocal over it and that's when the trouble begins.

I create a new track, put the setting usb mic (C-media usb mic) and then discover that all the tracks are lighting up when I talk into it. and it's awful and echoing.

Never happened in garageband.

Help! Gracias!