I feel compelled to relay an interesting experience that resurfaced to my memory after reading your post. I once, a number of years ago, was taping an album on my father's stereo system. After listening back to the tape after the recording was finished, I started noticing something VERY odd. Now keep in mind that this was a brand new cassette being recorded upon for the first time, but in between each track and at the fairly numerous quiet moments throughout the album one could hear conversations going on...distant, hollow and genuinely eerie in nature. Three seperate voices carried on, two of which were in the forefront with a third voice more distant. The words were just indistinct enough that the words could not be understood beyond syllables and vague phrasing. I listened to this tape many times, cranked the volume at the quiet spots to be sure it's what I was hearing and played it for a couple of friends to concur that what I heard was "what I heard" and see if we could discern the 'words' of the conversations...it freaked them out too. I have tried to apply rational explanations to the phenomena (radio interference, voices carrying through the structure from other parts in the house and onto the needle somehow(?), etc.). The most obvious theory could be traced to radio interference, but I have experienced that on numerous occasions and it really did not mimic this phenomenon. To this day, the memory of that tape stirs strange emotions in me.
Not too long ago I was reading about some enigmatic European eccentric who supposedly released recordings that documented what he believed to be voices from the spirit world that were found on blank cassette tapes. Though my experience involved recording voices onto a tape as opposed to being found on an unrecorded cassette, his ideas resonated with me at least a little bit as I thought back (again) to that strange recording.
