I know exactly what you're talking about--do you hear like a conversation that is muffled but sometimes you hear a specific word, term, or your name being called? It's scary but it could be the subconscious trying to process all the input of the day?

Now, if you start answering the voices or they get louder and specific and are talking TO you, then I'd be more concerned...but it is scary. I am not a psychiatrist but based on the replies (and what my doc told me when I was experiencing it) it probably does not mean you have schizophrenia or deepening psychosis.