This hobby is getting weird ....

I just finished listening to a CD through my headset which is plugged into the headphone jack on my integrated amp.
I also have the TV and a tuner connected to the amp. Both were shut off. When the CD was finished I didn't take the headset off right away. Then I could hear very faint voices, then music coming through the headset. Has anyone else ever experienced this, and what is it?
Sounds like you are picking up radio interference. This used to bug me no end.When I got a power conditioner it stoped , no more free radio, had to go out an buy an fm tuner. Sometimes it's the speaker wire /if coiled. I also used to get ham mobile radio guys,as the were passing by in their cars. I live on a busy street.
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 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.
Your right... this hobby may be making a "hard left turn" with no turn signal operable. Enjoyable reading though!
I think that a lot of cassets used to be made from recycled tape. Maye from an eight track or reel to reel.
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I once had a preamp that would pickup radio broadcast from Mexico or at least the language was spanish.
When I listen to music now I hear voices telling me to complain about Audiogon's voting policy.................
I think your head is discharging the sound back to the headphones. Sometimes it takes the entire lenght of the CD to get rid of it.
Centurymantra, The source of the "voices" you were hearing was probably athe residue of a mastertape that was not "fresh". Very often master tapes are "erased" and then recorded over. When you crank it up a bit you can often hear the "residue" of the previously "erased"
recording. I used to have a small recording studio, and have heard exactly what you described countless times.
Hornby... it was probably RF interference. Happens all the time. I doubt there is anything spooky going on here.
RFI, Radio Frequency Interference. It happens on many things, telephones, your sound system. You must have a radio station close by.

In days of old before cable, and it can still happen rarely with cable, when someone with a CB drove by it would come thru on the TV. Cars also used to drive by and you could hear and see the interference from the vehicle ignition on the TV.

Ever had a remote control car act weird when no one has the remote. It's a CB radio.

You might try some ferrite beads on your power line. Maybe on any interconnects. You can get them at RS.