It's not a question of lying, it is a question of analysis and interpretation.
However, our ears do lie. Of that we can be certain.
But let's start from the top. You think you heard a voice on a television show say something, not much to lie about, especially since everyone can go back and verify your claim. Noone has any problem with your experience, hearing a voice on tv, but big problems with your assumption it was paranormal and evidence enough the place investigated is haunted.
Even GH themselves in the early days was adamant pointing out EVP's alone is not evidence enough to deem a place haunted. To vague and sketchy to be solid evidence of itself. There isn't even a clear idea on how EVP's end up on tapes or HD's.
And I think it's healthy to be skeptical on what you hear on tv, since we can never be sure it wasn't added in post-production or simply a mishear on the part of the viewer. That's why EVP's have to have plenty of corroborative evidence to even be noteworthy.
As for GH telling it like it is, well, of that I am skeptical and that's why I participate on this site. In the early days, they might have wanted to tell it like it is, today it feels more like they tell it like it should be according to them in the way that is most entertaining, meaning the way that makes them the most money.