it just partially fixes the problem. Indeed I do not get disconnects from the iphone anymore. But now the router goes through power cycles. The iphone now causes these message.
Jan 28 00:50:37 Wireless system with Mac address XXX deauthenticate reason 3
Jan 28 00:50:15 Wireless system with Mac address XXX assoc success
Jan 28 00:50:15 Wireless system with Mac address XXX mc 1/16 uc 3/13 key 2 caps 0x0
Jan 28 00:50:15 Wireless system with Mac address XXX, sta authenticated
Jan 28 00:50:15 Wireless system with Mac address XXX recv auth frame with algorithm 0 seq 1
*I replaced the real MAC address with XXX
The result is, that existing SSH connections to remote hosts drop. This is very unpretty.
Victorinox... any ideas?