.htaccess and php.ini problem

Neither my custom rules in an .htaccess or php.ini file seem to be taking affect.

Certain Wordpress plugins have issues with gzip compression. The generic error I am receiving is this:
Warning: ob_start(): output handler ‘ob_gzhandler’ cannot be used after ‘URL-Rewriter’

I know the fix for this error, it involves disabling the session variables and gzip through either the .htaccess file or the php.ini file.

Unfortunately, after migrating to Dreamhost, the fix doesn’t seem to be working here. I’m assuming its some setting with the servers here, as all of my files are identical to what they were before.

Is there something I should be doing differently to get the .htaccess or php.ini file working?