It says that it's good for maximum 30 kg, but it's far away from that.
If you have speakers around 24 kg, it will let it tilt down.
I have an LD Systems ICOA 15 A.
It doesn't matter how strongly you tighten the bolts.
I installed an extra bolt to the hole, and now it's ok, because it's holding it in that position (in maximum tilt position). I also installed a chain, for emergency situations.