I just got a new RB951-2n, which won't complete a reboot. Instead, the ACT LED starts flashing a strange irregular sequence (1 long flash, then 1 short one, repeatedly). It seems like some error state code.

What does this LED flashing sequence mean, has anyone seen it, or perhaps support can explain?

The only way out of this flashing state, is to force a reset using the hardware button, which means I've also lost the configuration. I've tried it over and over, with different settings and variations, but still get the same thing every time I remove the power.

It worked fine the first time I power it on, and I used it fine for a while as I played with the settings, until the first time I rebooted it to use new settings file. Then I noticed the problem, but initially I assumed maybe I just did something wrong, and re-did all the settings manually instead after a fresh reset, but again got the same problem. I also had upgraded the firmware, before I realized it is a persistent problem.

With some trial and error, I've figured out that, when hard resetting it, if I release the reset button after a couple of seconds, instead of waiting for the LED to start flashing as instructed, I don't lose the config, and I get back to a working state with the most recent settings I made. However, of course, this is still not a practical solution, as I can't be doing this every time there is a power cut or whatever.

I've used an RB2011 before, and not seen this behavior.

Also, maybe unrelated, but there are no beep sounds as the router boots, as with the RB2011 I have. Does this model not have a beeper?

I've thought of a number of things that may or not be related, and fiddled around with them, but still no luck:
- Changing the boot-device between "flash-boot" and "nand". What should be the correct setting?
- I found this "auto-before-reset.backup" file, which I've tried deleting.

What's happening? Am I doing something wrong, or is it just a defective hardware unit?

Hi
Do you solved this problem?

Please post your output from /system routerboard print.

Make sure you have the latest RouterBOARD firmware.
You can upgrade it by,
/system routerboard upgrade
/system reboot
it can help fix your issue.