A strange issue with my webhost (which doesn't seem to have an idea either). I tried to increase the upload limit for the wp installation by changing values in the php.ini.
If I check which php.ini -file the site loads with
php_ini_loaded_file(), the call in wp-admin/upload.php returns "/usr/local/lib/php.ini", but the same function in the wp-content/themes/themefolder/header.php returns "/home/account694/public_html/php.ini"
The host uses a "shared" type of php.ini where all settings in a php.ini-file in the public_html -folder overrides the default ones.
I've checked that it isn't related to my own machine. How can this even be possible?