That`s just how it started, getting worse and worse. First it was like written above. Meanwhile I lost my whole WiFi functionality, said my touch can't connect to my wlan anymore. my wlan is unchanged since. every other device uses it. just the touch can't connect and doesn't tell my why. The reset of the network as described above is made twice but doesn't change anything. I already restored my touch in itunes with the last backup. The same - Can't connect. The WiFi is there, he recognizes my wlan, but can not connect and doesn't even asks me for the password - the next site with all the ip adress and so just stays empty.....
(Router is Dlink-524 if important)