1. Test with a different cable + adapter
Cheap USB-C-to-HDMI adapters from Hafeez Centre are the #1 cause of external display flicker in Pakistan. Borrow a known-good Apple or Anker adapter and test. If flicker stops, the adapter was the problem (replace with a quality one).
2. Check resolution + refresh-rate match
Some 4K displays at 60Hz over single-stream USB-C cause sporadic flicker. System Settings → Displays → check the resolution and refresh rate match your monitor's native spec. Lower to 30Hz if 60Hz flickers · usually it's a cable bandwidth issue.
3. M1/M2 Air dual-display limitation
MacBook Air M1 and M2 (A2337, A2681) only support ONE external display. Trying to drive two via a hub causes flicker on both. M3/M4 Airs and all Pros support 2+ external displays.
4. When the USB-C port is failing
After exhausting cable/hub fixes, the Mac's USB-C port itself may have wear damage. Try other ports on the Mac. If all fail, port repair PKR 6,000-10,000 fixes it.
5. Intel discrete GPU flicker
On 2018-2019 Intel MacBook Pros (A2141), the dGPU is known to flicker external displays as it ages. Symptom: flicker only when running heavy apps, syncs with system load. Fix: GPU reflow PKR 30,000-45,000.