OBi in reboot loop -- how can I recover?

[Stewart]

After attempting to load AA prompts "successfully" (with a possibly corrupt file), my OBi now continually reboots, even with only power connected.  It won't stay on the network long enough to access its web page.

When it was first in this loop, I looked at the network activity and saw:
DHCP Discover, Offer, Request, ACK (as expected)
KERN.INFO:  ==== Networking is ready ====\n\000
KERN.EMERG:  IP Address= 192.168.1.12 \000
KERN.EMERG:  Gateway   = 192.168.1.1 \000
KERN.EMERG:  Netmask   = 255.255.255.0 \000
KERN.ERR:  SYSTEM REBOOTED (lifecycle: 25)\n\000
LOCAL5.NOTICE:  ZT: CustomID 1\n\000
KERN.EMERG:  SLIC_init ...\000
KERN.EMERG:  Reset SLIC...\000
LOCAL2.INFO:  Setup Provisioning for system start! 1700\n\000
LOCAL1.ERR:  PARAM: Daemon is up ... state: 6 (f986c)\n\000
KERN.EMERG:  SLIC & DAA is initialized\000
KERN.INFO:  Start Main Service Now\000
KERN.DEBUG:  Voice Main\n\000
KERN.DEBUG:  [CPT] --- FXS s/w tone generator (ringback) ---\n\000
KERN.DEBUG:  BASESSL:load cert:5\n\000
KERN.DEBUG:  BASESSL:Load certificate ok\n\000
DNS      Standard query A root.pnn.obihai.com
DNS      Standard query response A 204.236.134.243
(start of registration with providers)
KERN.DEBUG:  XMPP:Invalid cfg use for xmpp\n\000
KERN.DEBUG:  GTT:xmpp not configured\n\000
(more SIP stuff)
KERN.DEBUG:  +++ malloc(8430445 bytes) failed c1bac\n\000
(above line repeated 8 times)
Then, after ~6 seconds, starts again with DHCP Discover.

So, I tried the paper clip.  It had some effect, because now I see:
DHCP Discover, Offer, Request, ACK
DNS      Standard query A root.pnn.obihai.com
DNS      Standard query response A 204.236.134.243
(the SIP and syslogs are gone)
Then, after ~7 seconds, starts again with DHCP Discover.

What should I try next?  Any sort of recovery firmware?
(As it repeatedly reboots with all cables except power disconnected, I'm pretty sure that the loop is not caused by something in my environment.)

Thanks in advance for any suggestions.

[RonR]

1. Remove power.

2. Using a paper-clip, depress and hold the reset switch accessible through the bottom of the unit.

3. Apply power.

4. Continue holding the reset button depressed for at least 30 seconds.

The unit should be reset to factory defaults.

[Stewart]

I had tried the long reset before, but just tried it again:

When power is applied with Reset held in, the Power light shows: solid red, then solid green, then flashing green, then faster flashing green, then back to solid red.  This repeats as long as I hold the button in (I tried for at least 5 reboot cycles).  The other indicators remain dark and the relay does not operate.

None of this helped.  Once I release the button, it goes through the same cycle I previously described.

Is any other simple manipulation possible?  Otherwise, what tools are available, e.g. TFTP-based, console port, JTAG, etc.?

[QBZappy]

Stewart,

Unless you want to have fun with opening up the box, I think that Obihai should replace the box if it is in this state as a result of the firmware. Opening the box might even have warranty implications. You don't strike me as a novice user. If this could happen to you it could certainly happen to me as well. I have a feeling that you would enjoy having a look inside. 

[Stewart]

Well, I discovered that the Web interface would work for ~3 seconds each reboot cycle.  The click when the failover relay energized told me when it was safe to click the mouse.  Over several reboot cycles, I navigated to the Device Update page, browsed to a backup copy of the user prompts and clicked the Update button.  A dialog box appeared, asking to click OK to update firmware (actually, the user prompts).  Then, on the next relay click, I clicked OK and it responded "User Prompts Update Successful"! Et voilà, after the reboot it didn't crash.

Now to get the config set up again (I was an idiot and didn't have a current backup).