Index: src/wp-includes/media.php
===================================================================
--- src/wp-includes/media.php	(revision 32484)
+++ src/wp-includes/media.php	(working copy)
@@ -2918,20 +2918,26 @@
 		}
 	}
 
-	$has_audio = $wpdb->get_var( "
-		SELECT ID
-		FROM $wpdb->posts
-		WHERE post_type = 'attachment'
-		AND post_mime_type LIKE 'audio%'
-		LIMIT 1
-	" );
-	$has_video = $wpdb->get_var( "
-		SELECT ID
-		FROM $wpdb->posts
-		WHERE post_type = 'attachment'
-		AND post_mime_type LIKE 'video%'
-		LIMIT 1
-	" );
+	if ( false === ( $has_audio = get_transient( 'has_audio' ) ) ) {
+		$has_audio = (bool) $wpdb->get_var( "
+			SELECT ID
+			FROM $wpdb->posts
+			WHERE post_type = 'attachment'
+			AND post_mime_type LIKE 'audio%'
+			LIMIT 1
+		" );
+		set_transient( 'has_audio', $has_audio );
+	}
+	if ( false === ( $has_video = get_transient( 'has_video' ) ) ) {
+		$has_video = (bool) $wpdb->get_var( "
+			SELECT ID
+			FROM $wpdb->posts
+			WHERE post_type = 'attachment'
+			AND post_mime_type LIKE 'video%'
+			LIMIT 1
+		" );
+		set_transient( 'has_video', $has_video );
+	}
 	$months = $wpdb->get_results( $wpdb->prepare( "
 		SELECT DISTINCT YEAR( post_date ) AS year, MONTH( post_date ) AS month
 		FROM $wpdb->posts