Batcache errors

I’ve just installed Batcache with APC and it’s working fine, except that the apache logs are filling up with errors like this:

[Mon May 28 16:45:59 2012] [error] [client 66.249.72.114] PHP Warning:  Cannot modify header information - headers already sent in /var/www/html/wp-content/advanced-cache.php on line 145
[Mon May 28 16:45:59 2012] [error] [client 66.249.72.114] PHP Warning:  Cannot modify header information - headers already sent in /var/www/html/wp-content/advanced-cache.php on line 146

NewRelic (the monitoring tool we use) provides this report. I don’t know where to start, I’m afraid.

I’m running the development version of Batcache, v2.03 of https://wordpress.org/extend/plugins/apc/ and WP 3.3.2

Here’s the stacktrace:

Error: Cannot modify header information - headers already sent

Sample stack trace

                in header called at /var/www/html/wp-content/advanced-cache.php (145)
in batcache::ob called at ? (?)
              in ob_end_flush called at /var/www/html/wp-includes/functions.php (3335)
in wp_ob_end_flush_all called at ? (?)
         in call_user_func_array called at /var/www/html/wp-includes/plugin.php (405)
                      in do_action called at /var/www/html/wp-includes/load.php (556)
in shutdown_action_hook called at ? (?)

Thanks for any help.