Clipping light comes on too early

Hello, my brother has a minor issue with his amplifier (ural warhead 1.1800), the clipping light on the remote comes on, but the sub doesn't get hot and doesn't sound weird. What could be faulty? IIRC there should be a comparator comparing the rail and output voltage, right?

Not planning on fixing it any time soon, just wanna know which component could be faulty.