I have bought a new LG G3 (D855, 16GB Flash, 2GB RAM), and rooted and flashed CM12.1 on it.
The phone works great (somewhat), but sometimes the screen turns itself off and the phone gets stuck in this state. Holding the power button neither turns the phone on nor off, and I have to remove and reinsert the battery to turn it on.
It has happened 7 times since Sunday.
I thought it might be due to overheating (a hunch), but could not find anything to confirm this.
How can I solve this problem?