bp_activity_media_fix_data()

function bp_activity_media_fix_data() {

	$privacy  = array( 'public', 'loggedin', 'friends', 'onlyme', 'grouponly', 'media' );
	$meta_query = array(
		array(
			'relation' => 'OR',
			'key'      => 'bp_media_activity',
			'compare'  => 'EXISTS',
		)
	);

	$result = BP_Activity_Activity::get( array( 'per_page' => 10000, 'privacy' => $privacy, 'meta_query' => $meta_query, 'show_hidden' => true ) );

	if ( ! empty( $result['activities'] ) ) {
		foreach ( $result['activities'] as $activity ) {
			$activity = new BP_Activity_Activity( $activity->id );

			if ( ! empty( $activity ) ) {
				$activity->privacy = 'media';
				$activity->save();
			}
		}
	}
}