TL-WR841N v13 Wi-Fi random disconnections

Issue: wi-fi randomly drops out in random intervals to the point I need to manually reboot the router, I can't even access the admin panel from tablet/phones.

It started out of nowhere on stock firmware a few days ago.
Thought migrating to custom ROM such as OpenWRT would fix it...
Doesn't matter what version I install — it is still the same.

This is likely a hardware failure since stock firmware doesn't work either. Try a different power supply as well before concluding the router is bad.

Try a different power supply as well

Why would I change it? Doesn't make any sense to me.