Happens to me a lot
On one occasion (when meditating) I found myself idly going down a shadowy tunnel until 'someone' really yelled at me. I came out of it quick-sharp and had a momentary flash of fear. Heaven alone knows where I was going - but I think someone stopped me in time
I get the voice thing often. Most of the time it's very meaningful.
Music happens to me all the time, too. On every occasion there is a clue to be found in either the words that perhaps go with that music or because it is associated with a specific person I know.
Here's a quick example - I woke up one morning with the words and music of a childhood song going round and round in my mind. It was 'London's Burning' - not sure if you'd know that one - but still
I had an early T'ai Chi class so dashed out of the house, picked up my friend and, as we were driving, told her about the song.
Later, when I was back at home my friend phoned me and asked me if I'd seen the mid-day news. I don't have television or radio on much so my reply to that was 'no'. Apparently, there was a fire on what will be the site of the London 2012 Olympics and the newscaster opened the program with the words 'London's Burning'.
Because I get this type of thing all the time, I write it down so I can keep track of it all. When I have any precognitive experiences, I also make sure I tell someone so that I can't be accused of making it all up after the fact