wp_get_attachment_image_src returns an array, not a single value. Please refer to this article for more info: wordpress.org/Function_Reference/wp_get_attachment_image_src
Default Usage
<?php
$attachment_id = 8; // attachment ID
$image_attributes = wp_get_attachment_image_src( $attachment_id ); // returns an array
?>
<img src="https://wordpress.stackexchange.com/questions/87552/<?php echo $image_attributes[0]; ?>" width="<?php echo $image_attributes[1]; ?>" height="<?php echo $image_attributes[2]; ?>">