Had the same problem. ADSL dropouts happened mainly when gaming or using torrents. Suspected that that it was due to limitations on the size of the port address translation table, so I reconfigured...

I get SNMP to work, but the support is rubbish. Using cacti with a raspberry pi to interrogate both my 8980 as well as my 8960N. In both cases the OID has not been implemented correctly, empty...