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Hardware: A1, f/w 1.02. Region is New Zealand (somewhere near Australia). We do Internet here the same as the 'States.
Haven't done a factory reset, but then I just bought it so what help would that do?
Internet / WAN:
We have DSL. I tried a simple DSL modem and also a very reliable old Dynalink modem/router/wifi. In both cases I set up the 810L as a simple DHCP client and also as a DMZ device, and was able to configure it to nicely do what I wanted. MTU is 1500, worked fine most of the time.
Router and Wired cfg:
Qos off, Advanced DNS off, DNS relaying ON. Some devices static IPs with higher numbers (printer, NAS), phones and laptops DHCP. Set the DHCP range to not overlap with the statics.
Firewall and intrusion OFF for now. uPnP On, Multicast On.
Locked WAN port to 100Mbps which seemed to help slightly.
Wireless:
Set up my own SSIDs (slightly different) for the 2.4 and 5Ghz bands. Left device modes, security, other settings default. Tried lowering power levels.
We have an old cordless phone - problems happen when phone inactive or in use.
Our house is in the countryside and the next nearest Wi-Fi network barely gets 1 bar onb our devices. Not an interference issue.
Modem is placed center of house. This location worked fine for old Dynalink. The 810L reported stronger signals also (except when it did it's drop-connection thing). Have moved it around a bit at this location, but no change in behaviour.