I have a Vigor 2920n running 3.6.3 firmware on my home network and providing a primary WiFi access point. In other parts of the house I have 2 other access points. One is a Netgear WPN802 and the other is a Linksys WAP54G. I have many WiFi enabled devices about the house including an iPad, iPhone4S, Internet radio, an android tablet etc. all of which work fine on any of the access points all of the time. I have FTTC from BT an get great bandwidth. I also have an HTC One X running android 4.1.1 which I normally only use on 3G but recently I have tried to use it via WiFi. Whenever I switch on the WiFi the Vigor 2920n either reboots or crashes its WAN connection with the ring of Act, WLAN, DoS,VPN,QoS,WAN2,CSM and USB lights all on steady green. I have to do a power cycle to clear the later. In either case I lose WiFi capability. Is there any fix for this?

3.6.3 firmware had issue with HTC phone with most models (in general terms) try firmware 3.6.1 or 3.6.4
ftp://ftp.draytek.com/Vigor2920/Firmware/

Many thanks. 3.6.4 seems to have done the trick. Looks like it is now working without crashing the router.

Having run with it most of the day I now find that none of my WiFi enabled kit will connect to the Vigor. Have reverted to 3.6.1 and this does seem to be working. At present I can connect to all of the access points including the Vigor and not crash it.