Errors from FastCGI on Apache 2.4.10 / Ubuntu 14.10

Greetings. I’ve been receiving several recurring errors in my /apache2/error.log relating to FastCGI, and it makes me think that I must have something misconfigured. On the front-end my site seems to load and function correctly and phpinfo(); shows my Server API as FPM/FastCGI. However, I’ve still been receiving errors.

The most common error being:

AH00524: Handler for fastcgi-script returned invalid result code 32

I also have a host of errors coming from my WordPress install that are outputting along the lines of:

FastCGI: server “/usr/lib/cgi-bin/php5-fcgi” stderr: PHP message: PHP …

But I’m a bit less worried about those, as they seem to be coming from specific WordPress plugins and strike me as less likely to be a misconfiguration on my end.

Any ideas about that invalid result code 32, though?

My /etc/apache2/conf-available/php5-fpm.conf looks like:

<IfModule mod_fastcgi.c>
  AddHandler php5-fcgi .php
  Action php5-fcgi /php5-fcgi
  Alias /php5-fcgi /usr/lib/cgi-bin/php5-fcgi
  FastCgiExternalServer /usr/lib/cgi-bin/php5-fcgi -host 127.0.0.1:9000 -pass-header Authorization

  <Directory /usr/lib/cgi-bin>
    Require all granted
  </Directory>
</IfModule>

Do I need to delete php5-cgi.conf, perhaps? I haven’t touched that file. In /etc/php5/fpm/pool.d/www.conf I did set

listen = 127.0.0.1:9000

and changed my user/group names to the appropriate ones, but didn’t change anything else in that file.

What am I missing? Anyone have any ideas?

Thanks in advance.