There are many televised debates which contain dialogue when played in reverse. Presidential debates, Special News reports and other programming have been tested and many have reverse audio present. My research leads me to believe that during this type of presentation or debate the person is reading a prepared text and that prepared text does not reflect the persons true feelings Trying to locate the origin of the R.A.P. is a difficult task. One area of investigation is the sound quality of the Voice. The Voice can sound Human and sometimes Paranormal in quality.
Some reverse voices sound as if the tonal inflections are slurred and garbled to a degree.
The accents are also different. But they are easily heard and understood with some practice. The electronic equipment and method use to investigate R.A.P. is basically this, you record on magnetic tape the conversation you want to investigate and you playback the tape in the reverse direction. Simple you say well think again. Many years ago I constructed a reverse tape recorder system, it worked well but was expensive and had limited controls.