These Speedport models W723V, W724V and W921V are only compatible with your eBlocker if you deactivate the DHCP server and setup your eBlocker individually, as well as use the DHCP server of your eBlocker. Please go to our knowledge base to find out how to configure your eBlocker individually.
Our forum-users report about a better stability after deactivating the windows IPv6 support in the network settings.