Potential Output Buffering Issue

I think I have an output buffering issue, but I don't understand it because in my php.ini file I have outbuffering = On .

[05/08/2013 11:16:01] E_WARNING: Cannot modify header information - headers already sent by (output started at /admin.local.com/show.php:1) in /admin.local.com/assets/init.inc.php on line 178

In my init.inc.php file I have:

<?php
ob_start();
session_start();

date_default_timezone_set("America/New_York");
setlocale(LC_MONETARY, 'en_US.UTF-8'); 
header('Content-type: text/html; charset=UTF-8');

$timer_start = microtime(true);

$path = dirname(__FILE__);


function custom_error_handler($errno, $errstr, $errfile, $errline){
	if (error_reporting() == 0){
		return;
	}

global $error_log_location;
	
ob_end_clean();