Can CodeIgniter change .htaccess all by itself?

[eluser]php_princess[/eluser]
My webhost lets us use PHP 5.2, 5.3, or 5.4. The choice is ours. We change the version of PHP through PHP Config in cPanel but what that does is update our .htaccess file in the root of public_html. Well, my PHP version mysteriously keeps getting set back to the default of 5.2, and I have to manually go and set it back to 5.4. My host is scratching their head as to why. They're asking me if I have any scripts that could be altering that .htaccess file.

This is my .htaccess at the moment:

# Use PHP5.4 as default
AddHandler application/x-httpd-php54 .php
RewriteEngine on

#RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
#RewriteCond %{REQUEST_FILENAME} !-l

RewriteCond $1 !^(index\.php|images|robots\.txt)
RewriteRule ^(.*)$ /index.php/$1 [L]

Right now my PHP version is 5.4, which is what it should be, and so far it's staying that way. The other day it had changed, once again, to 5.2 and I wish I'd known, then, to look in .htaccess because maybe I could see what happened. Maybe a script is deleting these two lines:

# Use PHP5.4 as default
AddHandler application/x-httpd-php54 .php

But I didn't look, so I don't know.

Thing is, I don't know any script of mine that would mess with .htaccess. Could CodeIgniter be the culprit?