Mark of the beast ping.
Today, believers through faith in Christ, are indwelt by all three persons of the Godhead. Simply by the language used in Scripture, this makes man in the Church Age, a temple of God.
One aspect of humanity which Satan cannot control is our ability to sin. When we step out of fellowship with God, either by simply thinking separately from Him, or by sinning, we have an opportunity for Him to forgive us those sins via the mechanics of 1stJohn 1:9. That forgiveness, allows God to futher His sanctification process of the believer. That process involves hearing the Word of God, The Holy Spirit making that Word spiritually perceived by faith in the believer’s human spirit, and also involves the development of inward knowledge in the mind as rationalism, and outward knowledge from the heart.
Technology now appears to have reached a point where it may be feasible to construct a communication system, which bypasses audible paths, but may intrude between what has been classically described as the mind and the heart, possibly between soul and spirit.
It appears that resolution of such communications would be dependent upon the proximity of the transmitter and the receiver or possible even to develop a transceiver for each recipient, similar to a cell phone but smaller, like a biochip.
For believers, allow no doubt in this regard. The mark of the beast will be marketed on both legalistic and moral issues. It will likely be marketed as for the general good of the world.
If a manmade device is developed which communicates a counterfeit message, as though it is from God, and it permanently interrupts the mechanisms God had put in place for us to have relationship with Him, through faith in Christ, the prophecies of Revelation regarding the removal of the Comforter, completion of the Church Age, and 2nd Coming all fall into place.
If you were wearing earplugs, you shouldn't be able to hear the sound. So that would be a good test as to whether the voice was from a supernatural source or a natural source.
That being said, current cell phone technology use a technique where they vibrate your jaw in order to send the sound to your ear. At least I believe that is what is happening.
So if the remote source can vibrate your jaw in the right way then it should be able to transmit a sound to your brain even if you were wearing ear plugs.
There is probably some way to damp out this form of transmission as well in order to make sure whether or not it is the voice of god.
Finally, if moving away from a certain spot causes the voice to go away, and then moving back to that spot causes the voice to return, then it is probably not from God.
Of course if they pay an agent to follow you around and constantly focus the sound point to where you are located, then you could become pretty paranoid rather quickly.