Interface Speed configuration issue

Hi,

We are using NetFlow Analyzer Distributed version 10.2.5. A issue I've come across is about the router interface speed.

First of all, SNMP strings are all set, but routers only get the interface speed at the first time, so if the interface speed changed, I've manually click on the router and click to update router interfaces using the SNMP get. Is there a way to schedule a daily or weekly scan on each router to update the interfaces speed?
Secondly, after I manually change a interface speed, the update router trick will not update the interface speed anymore, so if needed how can I set it back to sync with the SNMP get?

Thanks,
Justin T.