XPS 15-7590, LCD flickering on lowest brightness, #2

I have had the same issue as others - screen flickering in low brightness. I tried installing the latest Windows 10, uninstalling and re-installing Intel and nVidia drivers (as suggested by Dell Support), but nothing worked. I also tried adjusting the panel refresh settings from Intel's graphics panel and that also did not work.

However, I noticed that it only flickers when the laptop is running on battery power (and on lowest brightness). Doesn't flicker when brightness is increased or laptop is plugged in.

Unfortunately, I've decided to return the laptop as it had issues as well - no sound from internal speakers.

PS: For context, I had the 4K IPS display (with touch); i7-9750H