The Fritzbox 7490 has an approved bug, which ensures that your WLAN runs much slower after you connect your eBlocker to this router. This is not a bug that comes with your eBlocker. Other Fritzbox models are not affected with this bug.
The problem arises, if your eBlocker stays set in the automatic network-mode. Please click on the link below to find an instruction on how to set up the individual network setup: German / English
Another solution for Fritzbox 7490 users, is not to activate the 7490 WLAN and install a different WLAN access point into your network.