Audio Systems: Speaker issues, high pitch, car idling

Question
Just following up.  The site would not let me continue the previous dialogue, (too many follow up questions).  I can definitely say that the vibration sound starts at zero and increases as I increase the volume level.  Also, both speakers are doing this.  The speakers are about 6' apart, on separate shelves, in an entertainment center.  I previously listened to both speakers up close and they were both doing the same sound.  I even disconnected one speaker and then the other after getting annoyed by the sound.  The center speaker (Klipsch) still worked fine.  I have reset the wires four or five times to try and eliminate the sound.  I even bought the pins to put on the end of the wires instead of using the bare wires.

At one point, I did take the receiver and speakers out by themselves and hooked them up on the dining room table.  I used the same type of wires, just shorter.  The speakers seemed to work just fine.  The best way to describe the sound is a low humming sound.  Not really any squeal or high pitch.  Maybe somewhat similar to a car idling that does not have a muffler.

Answer
Sounds like hum induction caused by routing of the wiring.

Here is an experiment you could try:  Exchange one of the humming speakers with the center Klipsch (switch the wiring at the back of the amp) and see if the Klipsch now has the hum and the CV does not!  That can help you pin down what is going on.

Also, try dressing the wires differently making sure the speaker or other cables are not running parallel with a power cable.

The mystery is getting shorter!

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