Do you get any beeps when you hold the reset button in for several seconds, as in that article?
Also, I'd pull (and label) the drives in it while trying to reset or reflash it.
It appear the Synology machines do store their main operating system on the storage drives & the flash memory contains the boot and recovery system, if the stored system becomes corrupt.
That's another reason for trying it without drives connected?
More recovery info here; apparently the six pin header is a serial port!
I thought I'd post this here for anyone looking for help on troubleshooting a failed Synology Diskstation NAS. I've been a happy user of a Synology DS-212+. The software is robust and much better than my old DroboFS, and the...