SolarWinds is a great product.
Here are 3 possible causes:
» If you have a busy network check your router respond time - it should be lower than 50ms
» If you have a network bandwidth controlling device such as PacketShaper make sure you have created a Class (Inbound/Outbound) for SolarWinds and give the Class a Policy Priority(7).
» Check your firewall settings to be open for SolarWinds requirements.