My Fritz!Box 7270 (German company AVM) router is acting up very strangely. This happens with all connected Wifi devices.
For some time it even disappeared from some PCs Wifi access point tables! Sometimes I can't connect, Windows 7 says for example "could not connect to network X".
When it works, the connection is, again sometimes, very jittery or even breaking up.
When increasing the range I have to be connected already or I won't be able to connect. This is normal though, since it goes through like 3 walls this way.
This is a ping test to the router IP from a mediocre range (does not change even when being almost next to the box):
Reply from 192.168.1.254: bytes=32 time=181ms TTL=64
Reply from 192.168.1.254: bytes=32 time=6ms TTL=64
Reply from 192.168.1.254: bytes=32 time=577ms TTL=64
Reply from 192.168.1.254: bytes=32 time=39ms TTL=64
Reply from 192.168.1.254: bytes=32 time=5ms TTL=64
Reply from 192.168.1.254: bytes=32 time=150ms TTL=64
Reply from 192.168.1.254: bytes=32 time=639ms TTL=64
Request timed out.
Reply from 192.168.1.254: bytes=32 time=141ms TTL=64
Request timed out.
Reply from 192.168.1.254: bytes=32 time=18ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=2ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=120ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=8ms TTL=64
Reply from 192.168.1.254: bytes=32 time=3ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=105ms TTL=64
Reply from 192.168.1.254: bytes=32 time=90ms TTL=64
Reply from 192.168.1.254: bytes=32 time=51ms TTL=64
Reply from 192.168.1.254: bytes=32 time=50ms TTL=64
Reply from 192.168.1.254: bytes=32 time=111ms TTL=64
Reply from 192.168.1.254: bytes=32 time=61ms TTL=64
Reply from 192.168.1.254: bytes=32 time=350ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1021ms TTL=64
Reply from 192.168.1.254: bytes=32 time=41ms TTL=64
Reply from 192.168.1.254: bytes=32 time=618ms TTL=64
Request timed out.
Reply from 192.168.1.254: bytes=32 time=9ms TTL=64
Reply from 192.168.1.254: bytes=32 time=22ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1216ms TTL=64
As you can see, the connection is very jittery. Sometimes it works very well:
Reply from 192.168.1.254: bytes=32 time=8ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=7ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=3ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=4ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=4ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=3ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=2ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
Reply from 192.168.1.254: bytes=32 time=1ms TTL=64
This last test was done through one wall.
I don't know what I can do about this. I installed a new firmware on the router and it seemed to solve the problems at first. Then I got the jittery connection again. It didn't temporarily break up completely, yet, though.
This whole thing is almost not diagnosable... Anybody has any more ideas? I played around with all the Wifi settings, turning off Wireless N, etc. Even going insecure for a few minutes to test it, nothing.