I'm experiencing a persistent Ethernet link flapping issue on my EAP683's wired uplink port. The connected switch/router (MikroTik RB5009) logs the port going link-down and link-up every few minutes, sometimes multiple times per hour, with the link always renegotiating cleanly back to 1Gbps full duplex each time.

Troubleshooting performed so far, all of which point to the AP itself rather than the cabling or switch side:

• Tested 4 different cables (1x Cat7, 3x newly-made Cat6 straight-through) — same flapping behavior on every cable.
• Moved the cable between multiple switch ports (Ether 5 to 8 on the MikroTik) — flapping followed the AP to each port, ruling out the switch/router ports.
• Other devices connected to the same switch ports remain completely stable with no link drops — only this AP causes flapping, regardless of port or cable.
• Swapped the AP's power adapter (not using PoE, using a separate 24W adapter) — no change.
• Confirmed via the Omada controller's Device Connected/Disconnected events that the AP itself never disconnects from the controller during these flaps — the AP's system and wireless service stay fully online throughout.
• Checked the AP's own interface counters via SSH (cat /proc/net/dev) — eth1 (wired uplink) shows 0 hardware errors, only a negligible drop count (32 drops out of 1.6M+ packets).
• Checked kernel logs via dmesg | grep -i eth and dmesg | grep -i link on the AP — no link-state transition events logged at all, despite the switch-side logs clearly showing the port going down and up repeatedly.