WXR-1900DHP not manageable via ethernet

[bard]

I recently purchased a WXR-1900DHP and when I connect my laptop via ethernet, I get an IP address (192.168.11.2) but I cannot ping or http to the device @ 192.168.11.1.

I can however use wireless to connect to, manage, and configure the device.  This is using "default" settings (after using the reset button).  The switch on the bottom is set to router. I've used dozens of Buffalo products over the years, but this is behavior I've not seen before. 

For what it's worth, I can directly connect the same device using the same cable and same configuration to my WZR-600DHP2 and everything works just fine.  So it's not the device, nor is it the cable. I can see via WireShark that DHCP is functioning correctly.  I'm at a complete loss as to what is wrong.

Thoughts?

[bard]

Ok, I sent that one back to Amazon and got another one.  The first time I turned it on I was able to connect via Ethernet to 192.168.11.100 even though the default gateway it provided was 192.168.11.1 via DHCP.  This was with the switch on "Router".  So I then moved the switch through each position power cycling each time.  When I got back to "Router" I tried again to manage the router via ethernet.  Airstation config tool identifies the router at 192.168.11.1 now and it is not reachable via web management at that IP.  It doesn't respond to ping at that address either.  NMAP shows 443, 80, and 53 TCP open on 192.168.11.1.  I can see via wireshark the requests being made, but the router does not respond.  Periodically, the router will multicast SSDP, so it is functioning on some level.  And when I attach via wireless, it all works perfect, unfortunately I need it to work both wired and wireless!

[bard]

Ok, flashed router to latest firmware (2.37).  Same problem. Debug interface is gone, password changed, now I can't even effectively troubleshoot. 

After years of using buffalo products, I'm very disappointed.  I can't flash to a firmware that actually works (dd-wrt) I guess I'll return this one to amazon as well and get something else.  Any recommendations?

[bard]

Does tftp firmware flash even work on this router?  It broadcasts the request for firmware.ram but then ignores all packets sent to it.  Has anyone got tftp firmware flash to work on EXR-1900DHP?