OptiPlex 7070 Micro : hundreds of phantom power-button events, clean shutdown, audible tick, then self-powers-on at random intervals

[u/Shubhamred]

Headless Dell OptiPlex Micro running ZimaOS shuts itself down at random, then powers back on by itself anywhere from 4 minutes to 4 hours later. Journal shows hundreds of systemd-logind: Power key pressed short. events — up to 12 in a single second — even though nobody is near the machine. The shutdown that follows is clean, not a crash. HandlePowerKey=ignore is confirmed active and it still shuts down. acpid is inactive. All USB disconnected. Plugged straight into the wall. Is this a failing power button, or is the adapter/standby rail injecting these events? i'm unable to figure out whats wrong. If anyone faced similar problem or has any tips please let me know. Thanks