@lrhodes God damn it, things always break when you least expect them to. Replacing it with the same model doesn't seem like an option — it's too old, TBH it turned out futureproof indeed — never felt the urge to replace it until now. Sometimes I started eyeing WRT3200ACM — but now that's an old model too, nearly impossible to hunt down. I'm really reluctant to replace it with something new and not known to work well with OpenWRT — I'll try replacing the power adapter, hope it would do the trick.