Muscle Sensor picking up only noise

I got the MyoWare Muscle sensor, and its only picking up noise. Worked briefly with a USB isolator, but not quite sure why the sensor is picking up straight noise. Suggestions?

How is it wired up? Share some photos

Try testing with a battery-powered source if you can (laptop, etc)
Are you using REF?

There are MANY notes about how to hook it up, see our guide
Also: Quickstart guide ; Advanced guide