Thanks Umbral and Perna. I also think it's anxiety-related, and not a psychotic-type hallucination. It's still very annoying, and at times, impossible to ignore. I try to meditate and need silence for that. I just started gabapentin for it, an anti-seizure medication. I'll see if that does anything. On one occasion, a stronger than usual dose of xanax knocked it out for a while. I don't like to take tranquilizers any more than necessary.