Social Icons Hover Tag

How do I change the hover ALT tag on the social icons? I figured out how to "hack" the social icons to get ones I want. I replaced the Myspace icon in the actual image with a Yelp button and it works fine. But the ALT tag still says MySpace. I've found all instances of MySpace in the code and changed them and nothing changed. <label><?php _e( 'MySpace', 'catchbox' ); ?></label></th> Is this not it? How do I change the ALT tag? Thanks.