diff --git a/wp-admin/edit-form-advanced.php b/wp-admin/edit-form-advanced.php
index 7f0ea62f6a..b1d0bf57fa 100644
--- a/wp-admin/edit-form-advanced.php
+++ b/wp-admin/edit-form-advanced.php
@@ -140,7 +140,7 @@ if ( 'attachment' == $post_type ) {
 	add_meta_box( 'submitdiv', __('Save'), 'attachment_submit_meta_box', null, 'side', 'core' );
 	add_action( 'edit_form_after_title', 'edit_form_image_editor' );
 
-	if ( preg_match( '#^audio#', $post->post_mime_type ) ) {
+	if ( 0 === strpos( $post->post_mime_type, 'audio/' ) ) {
 		add_meta_box( 'attachment-id3', __( 'Metadata' ), 'attachment_id3_data_meta_box', null, 'normal', 'core' );
 	}
 } else {
diff --git a/wp-admin/includes/media.php b/wp-admin/includes/media.php
index 47bbfdb509..91d558618a 100644
--- a/wp-admin/includes/media.php
+++ b/wp-admin/includes/media.php
@@ -2662,7 +2662,7 @@ function edit_form_image_editor( $post ) {
 	<div class="wp_attachment_details edit-form-section">
 		<p>
 			<label for="attachment_caption"><strong><?php _e( 'Caption' ); ?></strong><?php
-			if ( preg_match( '#^audio|video#', $post->post_mime_type ) ): ?>: <?php
+			if ( preg_match( '#^(audio|video)/#', $post->post_mime_type ) ): ?>: <?php
 				_e( "Custom label for item in a playlist. If empty, the file's available data is used." );
 			endif ?></label><br />
 			<textarea class="widefat" name="excerpt" id="attachment_caption"><?php echo $post->post_excerpt; ?></textarea>
@@ -2688,7 +2688,7 @@ function edit_form_image_editor( $post ) {
 	?>
 
 	<label for="content"><strong><?php _e( 'Description' ); ?></strong><?php
-	if ( preg_match( '#^audio|video#', $post->post_mime_type ) ): ?>: <?php
+	if ( preg_match( '#^(audio|video)/#', $post->post_mime_type ) ): ?>: <?php
 		_e( 'Displayed on attachment pages.' );
 	endif ?></label>
 	<?php wp_editor( $post->post_content, 'attachment_content', $editor_args ); ?>
@@ -2751,7 +2751,7 @@ function attachment_submitbox_metadata() {
 			<?php
 		endif;
 
-	if ( preg_match( '#^(audio|video)#', $post->post_mime_type ) ):
+	if ( preg_match( '#^(audio|video)/#', $post->post_mime_type ) ):
 
 		/**
 		 * Filter the audio and video metadata fields to be shown in the publish meta box.
diff --git a/wp-admin/includes/meta-boxes.php b/wp-admin/includes/meta-boxes.php
index f91df90347..f690f8b7e7 100644
--- a/wp-admin/includes/meta-boxes.php
+++ b/wp-admin/includes/meta-boxes.php
@@ -1071,7 +1071,7 @@ function attachment_id3_data_meta_box( $post ) {
 		$meta = wp_get_attachment_metadata( $post->ID );
 	}
 
-	foreach ( wp_get_relevant_id3_keys() as $key => $label ): ?>
+	foreach ( wp_get_relevant_id3_keys( $post ) as $key => $label ): ?>
 	<p>
 		<label for="title"><?php echo $label ?></label>
 		<input type="text" name="id3_<?php echo esc_attr( $key ) ?>" id="id3_<?php echo esc_attr( $key ) ?>" class="widefat" value="<?php
diff --git a/wp-admin/includes/post.php b/wp-admin/includes/post.php
index bf59a9a162..55747271a6 100644
--- a/wp-admin/includes/post.php
+++ b/wp-admin/includes/post.php
@@ -237,19 +237,15 @@ function edit_post( $post_data = null ) {
 		}
 	}
 
-	if ( 'attachment' === $post_data['post_type'] && preg_match( '#^audio|video#', $post_data['post_mime_type'] ) ) {
+	if ( 'attachment' === $post_data['post_type'] && preg_match( '#^(audio|video)/#', $post_data['post_mime_type'] ) ) {
 		$id3data = wp_get_attachment_metadata( $post_ID );
 		if ( ! is_array( $id3data ) ) {
 			$id3data = array();
 		}
 
-		foreach ( wp_get_relevant_id3_keys() as $key => $label ) {
+		foreach ( wp_get_relevant_id3_keys( $post ) as $key => $label ) {
 			if ( isset( $post_data[ 'id3_' . $key ] ) ) {
-				if ( current_user_can( 'unfiltered_html' ) ) {
-					$id3data[ $key ] = wp_unslash( $post_data[ 'id3_' . $key ] );
-				} else {
-					$id3data[ $key ] = wp_unslash( wp_kses_post( $post_data[ 'id3_' . $key ] ) );
-				}
+				$id3data[ $key ] = sanitize_post_field( wp_unslash( $post_data[ 'id3_' . $key ] ) );
 			}
 		}
 		wp_update_attachment_metadata( $post_ID, $id3data );
diff --git a/wp-includes/media.php b/wp-includes/media.php
index 6c1ddaeb01..4b4fd956c8 100644
--- a/wp-includes/media.php
+++ b/wp-includes/media.php
@@ -1016,25 +1016,25 @@ function wp_underscore_playlist_templates() {
 ?>
 <script type="text/html" id="tmpl-wp-playlist-current-item">
 	<# if ( data.image ) { #>
-	<img src="{{{ data.thumb.src }}}"/>
+	<img src="{{ data.thumb.src }}"/>
 	<# } #>
 	<div class="wp-playlist-caption">
 		<span class="wp-caption-meta wp-caption-title">&#8220;{{{ data.title }}}&#8221;</span>
-		<# if ( data.meta.album ) { #><span class="wp-caption-meta wp-caption-album">{{{ data.meta.album }}}</span><# } #>
-		<# if ( data.meta.artist ) { #><span class="wp-caption-meta wp-caption-artist">{{{ data.meta.artist }}}</span><# } #>
+		<# if ( data.meta.album ) { #><span class="wp-caption-meta wp-caption-album">{{ data.meta.album }}</span><# } #>
+		<# if ( data.meta.artist ) { #><span class="wp-caption-meta wp-caption-artist">{{ data.meta.artist }}</span><# } #>
 	</div>
 </script>
 <script type="text/html" id="tmpl-wp-playlist-item">
 	<div class="wp-playlist-item">
 		<div class="wp-playlist-caption">
-			{{{ data.index ? ( data.index + '.&nbsp;' ) : '' }}}
+			{{ data.index ? ( data.index + '. ' ) : '' }}
 			<# if ( data.caption ) { #>
 				{{{ data.caption }}}
 			<# } else { #>
 				<span class="wp-caption-title">&#8220;{{{ data.title }}}&#8221;</span>
 				<# if ( data.artists && data.meta.artist ) { #>
 				<span class="wp-caption-by"><?php _e( 'by' ) ?></span>
-				<span class="wp-caption-artist">{{{ data.meta.artist }}}</span>
+				<span class="wp-caption-artist">{{ data.meta.artist }}</span>
 				<# } #>
 			<# } #>
 		</div>
@@ -1203,7 +1203,7 @@ function wp_playlist_shortcode( $attr ) {
 		$meta = wp_get_attachment_metadata( $attachment->ID );
 		if ( ! empty( $meta ) ) {
 
-			foreach ( wp_get_relevant_id3_keys() as $key => $label ) {
+			foreach ( wp_get_relevant_id3_keys( $attachment ) as $key => $label ) {
 				if ( ! empty( $meta[ $key ] ) ) {
 					$track['meta'][ $key ] = $meta[ $key ];
 				}
@@ -1317,9 +1317,10 @@ function wp_get_audio_extensions() {
  *
  * @since 3.9.0
  *
+ * @param WP_Post $post The post in question, provided for context.
  * @return array
  */
-function wp_get_relevant_id3_keys() {
+function wp_get_relevant_id3_keys( $post ) {
 	$fields = array(
 		'artist' => __( 'Artist' ),
 		'album' => __( 'Album' ),
@@ -1327,14 +1328,16 @@ function wp_get_relevant_id3_keys() {
 		'year' => __( 'Year' ),
 		'length_formatted' => __( 'Formatted Length' )
 	);
+
 	/**
-	 * Filter the editable list of keys to lookup data from an attachment's metadata
+	 * Filter the editable list of keys to lookup data from an attachment's metadata.
 	 *
 	 * @since 3.9.0
 	 *
-	 * @param array $fields
+	 * @param array   $fields Key/value pairs of field keys to labels.
+	 * @param WP_Post $post   Post object.
 	 */
-	return apply_filters( 'wp_get_relevant_id3_keys', $fields );
+	return apply_filters( 'wp_get_relevant_id3_keys', $fields, $post );
 }
 /**
  * The Audio shortcode.
@@ -2331,7 +2334,7 @@ function wp_prepare_attachment_for_js( $attachment ) {
 			$response['fileLength'] = $meta['length_formatted'];
 
 		$response['meta'] = array();
-		foreach ( wp_get_relevant_id3_keys() as $key => $label ) {
+		foreach ( wp_get_relevant_id3_keys( $attachment ) as $key => $label ) {
 			if ( ! empty( $meta[ $key ] ) ) {
 				$response['meta'][ $key ] = $meta[ $key ];
 			}