Yes, of course this is quite common. I have experienced this myself.
I'll write this response for all those who are uncomfortable with this symptom.

Your voices are your own thoughts, they come form your own mind, memory and imagination. This thoughts become dissociated most probably because of a deep anxiety within you, a very deep anxiety. Again I previously had these symptoms and i discovered that all my symptoms were driven or manifested because of deep fear and anxiety.

Every human bing schizophrenic or not naturally goes towards what is unsolved or unresolved in their experience So it is quite common to experience voices as 'negative', being that they are the rising energy of unresolved negative experiences.
You probably cannot control whether or not you have voices but you can develop and acceptance of yourself and feel happier. As such learning how to talk to yourself about you negative experience can help you with this. In that case if you can talk with a therapist about your negative experience and how to deal emotionally with negative criticism then you can find yourself more at peace with the voices.

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As for myself, I no longer experience Schizophrenic symptoms. I phased out pharmaceuticals concurrent with psychotherapeutic progress and actually got a sign off of "sanity' from two psychiatrists as and explanation to the social assistance which was transferred to the regular department for a while before I became independent.

I resolved some major conflicts and I learned to have and enjoy all my emotions occluding the negative ones.
If I did hear voices now,I would much enjoy the experience, but I suppose by the contrarian rules of 'Mother Nature' I am denied a free sensational experience' and must endure normalcy and actually make involvements of some kind to have emotional experiences.

I can say another thing - when I lost my "voices" and anxiety by means of medication I functioned, yes, but I was very emotionally dead - I barely remember the time that passed because it was emotionally meaningless. The root of my life was in the anxiety and fear - to get rid of that was to get rid of me. I did appreciate the relief though - the only problem was it went on too long without therapeutic help and it was to deep. It's better to have a little symptom left to have a little life to deal with.
The idea that 'negative' emotions can be medicated away and then a person will be 'positive' is simple minded and destructive. Without the negative, the positive cannot have any energy, what is left is mediocrity at best.

I certainly don't impose the idea that everyone can be like myself, but I do think there could be a lot more that could achieve the same, especially as I do not see very many people, both helpers and patients as pursuing what I consider to be 'growth processes'.
I open these thesis statements for inspection.

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Take care and good luck to you.You show a capacity for cogent thought which is very promising. I can tell you I could not have been as cogent or aware when I was a Schizophrenic - you are evidencing a much higher level than I ever had.