what can you do shabbos if your alarm went off very loud, and is making your house a gehenom for everyone in the house, and waking everyone in middle of the nite isn’t an option, covering with a pillow will turn it off, maybe because it’s not a melocha shetzurech legufo, its permissible to turn the volume knob to very very low
There are a number of possibilities to deal with this situation:
1 moving the clock to a place it will not disturb, a different room, even outside
2 covering it, if a pillow will turn it off, maybe cover with a box, and cover that with blankets, etc.
3 having a non Jew turn it off
4 if there are children being disturbed and all of the above are not a possibility, allowing the child to turn it off
Lowering the volume and turning it off would be in the same category, if it is a desperate situation and all of the above are totally not options, there may be room for leniency to turn it off/unplug it in an abnormal fashion [with one’s foot etc.]