interclass74 You can try change this in /templates/ja_events_ii/tpls/blocks/header.php file :
<header id="t3-header" class="wrap t3-header-wrap affix-top cpanel-close" data-spy="affix" data-offset-top="1">
to
<header id="t3-header" class="wrap t3-header-wrap cpanel-close">
Ensure to clear your browser cache if changes dont reflect