Loglevel value in config.php ignored

Steps to reproduce
1. config.php: 'loglevel' => 4
2. Webserver restarted (should not be required, but ...)
3.

Expected behaviour
owncloud.log: no more log lines marked as "level":3

Actual behaviour
still a lot of log entries marked as "level":3

Server configuration
Operating system: Debian GNU/Linux testing (stretch)
Web server: Apache/2.4.23 (Debian)
Database: 10.0.27-MariaDB-0+deb8u1 (Debian)
PHP version: PHP 7.0.10-1
ownCloud version: 9.1.0.15
Updated from an older ownCloud or fresh install: updated from 9.0.5

ownCloud log (just 1 line shown):
{"reqId":"5fJ8GgXbvMWg1qR+ynLS"
,"remoteAddr":"93.104.57.113"
,"app":"no app in context"
,"message":"Error getting storage info for mount at hidden"
,"level":3
,"time":"2016-09-18 11:44:20"
,"method":"PROPFIND"
,"url":"\/owncloud\/remote.php\/webdav\/"
,"user":"hidden"
}

Special configuration (external storage, external authentication, reverse proxy, server-side-encryption): external storage of type "local"

Integrity status for oC9+
No errors have been found.

Please report a new issue to https://github.com/owncloud/core/issues

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