To be fair, I have only heard voices a few times in my whole life. I am certainly not plagued by them luckily.
Meditation is like a concentration of the mind. You focus on one thing. At first for voice hearers that might get worse, but in the long run concentrating on the tip of your nose for example for long periods might lessen them.
@Om_Sadasiva has said that at first it gets worse and then it quietens, i think.
Iâm a Stoic and we do a form of meditation called negative visualization. We envision negative things happening so if something bad does happen youâre prepared and you can have some control over your reaction.
I donât believe meditation opens you up to demonic influences. Having a clear mind helps you tap into your own subconscious thoughts and desires, and to formulate a plan around them. Hard to do that when you hear voices though.
Buddhists believed that meditation was the way to Nirvana, even.