No, he said he wasn't referring to the literally insane people who claim to hear the voice of God. It's a seemingly minor distinction, but very important!
I don't think he was saying - or at least I didn't infer it - that in those cases it was the hearing alone that means they are insane. They are legitimately insane... and they ALSO hear God speaking to them. Which almost certainly is a real thing. Actually it is... there was a guy here on CC who claimed that God was telling him some pretty unbiblical things.
I've heard a voice speaking to me a couple times. Audibly, or in my mind? I don't know. The one time, I was asleep and I heard my name spoken softly. I instantly was completely awake. It felt like I was hearing it with my chest. That's the only way I can really describe it. I didn't know what to do or think, but it was not a normal thing. Afterwards I would remember the account of young Samuel in the Scriptures, but I don't remember having a repeat of that moment again like Samuel did.
I do have a vague recollection of a voice in association with something I was told to do. It's fuzzy in my mind so I'm not going to talk about it in detail. I was told to go into the downtown area of Baltimore and share the gospel. I wasn't particularly excited about that and put it off for a long time. It got to the point where it was always in my head, though. I couldn't shake the thought that I needed to go there for some reason. Finally I went for my sanity's sake.
I passed out gospel tracts for a couple of hours to mostly disinterested people around lunchtime. But then I wandered into a more depressed neighborhood, and in an alley between two apartment buildings I saw a young guy and felt like I needed to talk to him. We ended up talking for about an hour about his life and the gospel. Turns out he was a drug dealer but for a while he had felt like he needed to make a change in his life for the sake of his kid. He didn't become a Christian on the spot or anything like that, but I was astounded to see him crying when I shared the gospel with him.
After I spoke with him, I felt like I was "off the hook" so to speak. I knew I was done with what I needed to do so I went home. One of the stranger experiences of my life.