ob_get_clean(): failed to discard buffer of _shutdown_function

After updating Creative theme to version 1.3 and deleting few unused modules, I noticed a message when I log out.

Notice: ob_get_clean(): failed to discard buffer of _shutdown_function (2) in theme_render_template() (line 1520 of ... theme.inc).

The website layout changed, the content of some blocks is displayed on the top page (wrong place). See the screenshot.
There is not much info on this problem on the web. If anyone has ideas how to deal with this issue please post your suggestions.

Thank you.