Social Icons Hover Text

Having some trouble changing the text on the social icons. I have replaced the RSS icon with a custom icon and that works fine. However the hover still says RSS. I have tried changing it in the catchbox-functions.php but no luck. What am I missing here?

//RSS
			if ( !empty( $options[ 'social_rss' ] ) ) {
				$catchbox_social_networks .=
					'<li class="rss"><a href="'.esc_url( $options[ 'social_rss' ] ).'" title="'. esc_attr__( 'IMDB', 'catchbox' ) .'" target="_blank">'. esc_attr__( 'IMDB', 'catchbox' ) .'</a></li>';