Mikrotik reset sound on every boot, can't connect to it

Hi everyone,
I have a RB951G-2HnD, it worked for an year, I updated it to the last RouterOS v6.42. It worked until first reboot. Then I couldn’t connect to LAN ports anymore, WiFi does not turn on, only a single beep and no two beeps. Every 5 mins it restarts itself. LEDs are blinking but no winbox, no DHCP, nothing. I have posted more topics like this but this is a different issue on a completely different device from a different location.

  1. I tried to reset the config with reset button, no luck
  2. I tried to reset it with metal pad, it does the “reset sound”, but it still wasn’t booting default config and was not reachable
  3. I got netinstall up and running, the device shows up in neinstall, reflashing went smooth.

It is still not reachable and now it makes a “reset sound” everytime it boots. Ethernet LEDs are blinking, single beep and souble beep sounds sound normal. No DHCP, no WiFi, no bridge between LAN ports. Can’t connect with Winbox and it does not show in Netinstall anymore.

What can I do next?

I released the button after 19.5 sec not 20.5sec and it showed up in netinstall again. Second flash went smooth and now it boots to default config, hurray. Thank you all.

I miss serial ports, it was so nice to see what’s happening.