New BETA firmware for DGL-5500 v1.13.b02. Visit it's board for more information.
@OP: I want some back up for your ideas of what to turn off. For example, why turning of Dynamic Fragmentation, is that enough or turning off QoS entirely better? Issue with WPS, I haven't heard too. So give some reason please so ppl can check what is the most likely culprit for their unstable DIR-655.
I have my channel set to specific one.... My thinking is that anything that might cause the router to change channels (other than a reboot) would likely cause a disconnect to the wireless clients.
I have my Visibility Status set to be invisible....makes it that much harder for anybody to try and connect that isn't allowed,.....
I have Router QOS engine turned off.....
An invisible SSID really provides very little security protection. You're better off leaving visibility on and using WPA or preferably WPA2 for security. Some wireless clients don't handle a hidden SSID well.
I setup all wireless manually with static IP's and never have a problem with any of them. Clients do not need to "see" the SSID if it is already in their configuration.
I use a 63 long key which you can get from https://www.grc.com/passwords.htm and use WPS with PIN to register clients.
Hiding has very little security benefit and causes problems for some.