I've got a php site where I've used php include to include a header, a menu, and a footer. The header has the starting tags like <html> etc.
This worked fine, however, when checking the site today, I noticed a gap between the header and menu that I cannot explain.
Upon inspecting it in Chrome, the <title> etc tags are in the <body> tags, not the <head>, and (I think) between the header and menu includes, and before the closing of the content tag, there's  that I have no idea what is, nor where came from.
If I take the content from the header, menu, and liner files and paste it in instead of the php include, it all works fine, no problems what so ever. The mystery code above also vanishes. (I've also tried removing the FB code, did nothing).
For referrance, here is a link to a copy of the site on my own domain. The test with everything pasted can be found here. The parts included are header.php, menu.php, and liner.php. The code before the content div;
<?php
include("header.php");
?>
<?php
include("menu.php");
?>
and the code after it;
<?php
include("liner.php");
?>
If anyone can help out with this, I would be very grateful. I'm very lost. Thanks!