This looks like a css conflict with your template stylesheet.

Please post a link to your site front-end so I can check the template stylesheet (no login required)

Thank you Ryan. My client's site is at http://www.academysingers.com.au The template: http://www.shape5.com/demo/business_line/

The template style appears to have some inline css (not part of the main stylesheet) where it is applying a style to the <button> tag, eg:

.readon, .button, button, .s5_ls_readmore, .dropdown-menu li > a:hover, .dropdown-menu li > a:focus, .dropdown-submenu:hover > a, .dropdown-menu .active > a, .dropdown-menu .active > a:hover, .nav-list > .active > a, .nav-list > .active > a:hover, .nav-pills > .active > a, .nav-pills > .active > a:hover, .btn-group.open .btn-primary.dropdown-toggle, .btn-primary, .item-page .dropdown-menu li > a:hover, .blog .dropdown-menu li > a:hover, .item .dropdown-menu li > a:hover, .btn, .pagenav a, .ac-container label:hover, .ac-container2 label:hover, .jdGallery .carousel .carouselInner .active, p.readmore a:hover, .s5_is_css_10 .s5_is_slide_css_plus_circle:hover, .progress_bar3, .s5_tab_show_slide_button_active, .steps_boxes_highlight1, .module_round_box.highlight1 {

    background:#1EA0FB !important;

}

The !important property is bad practice here, as it prevents the style from being overridden by anything else, which is fine for specific css, but not when applied directly to a tag, ie: button in the css selector.

You will need to remove button from the css selector for this rule if you can, otherwise you will have to live with blue buttons in the editor toolbar.