That happens to me alot man. I always have auditory hallucinations when I'm really high. Sometimes it's leftovers from people I talked to earlier in the day, sometimes it's just sounds, and sometimes it's actual noises like the house popping or something and it seems amplified. Sometimes I think I'm having OEV's but it's really just a shadow that I caught out of the corner or my eye or something, it's really nothing. I had a bad wreck about two years ago in which I broke my back, completely destroying some nerves and having to live with that pain for the rest of my life. Some mornings I can't even get out of bed and I'm only 20. That's fairly traumatic, so sometimes I actually hear the car crashing in my head. That's the only time the auditory hallucination's bother me, when that happens I find myself getting sweaty and little lightheaded but I control it now. I'd much rather be completely blazed and not have to feel my back. It's fairly normal, doesn't mean you're going crazy, just watch your perception of it, that's where the only danger lies.