Normis mentioned PHPBB 3.1.9 is used: http://forum.mikrotik.com/t/why-are-bbcode-code-blocks-inserting-a-space-at-the-start/97809/1
Since that supports ATOM feeds, please enable those as it makes it way easier to track threads.
More information is at https://www.phpbb.com/support/docs/en/3.1/kb/article/faq-phpbb-atom-feeds/
–jeroen