I'll explain. The minimum update period for CyberSyn is 300 seconds (5 min). So it won't update more frequently in order to prevent your server from possible overloading.
Also if you are using "auto updates", then it doesn't mean that your blog will be updated exactly withing the given period. It will be updated only when someone opens your blog in browser. This will invoke the update routine which will check if it's time to update your blog or not. So it won't update it exactly in the given period (course if your your blog doesn't have at least one hit per 5 minutes).
On other hand,
there is a way to make your blog update exactly when you want. In this case you must use "update by cron" option on the blog setting page.
Hope it helps.
BTW, feel free to ask your questions/report bugs/request for additional features right at
http://www.cyberseo.net/cybersyn/
Thank you.