Hi Chris,
it gets pretty complicated when it comes to triggers for hearing voices and the cause.
I had never heard a voice before in my life prior to that 2 month time when I was recording for EVP....same for many of the others I know.....most of us started hearing them with just our ears pretty fast....within just a matter of weeks or months...but I met one person who was doing EVP for years and then it happened to them to...so it seems like there are common patterns here....but exceptions seem to occur as well.
I don't know what makes a person more vulnerable really....for a while I thought maybe it was drugs or such that I did when I was younger...but then I've met a guy who started hearing the voices after using a pendulm and another who used a spirit box who were sober their whole lives....I've always felt in my case it was at least in part that I was doing EVP sessions so often with that same group of spirits/entities..and I attuned my hearing to them very quickly. That and that I didn't recognize what they were up to until it was too late.
I think any type of grounding or protection is still a big if....I mean if we don't know who are what all of these spirit entities are...how would we know if we're protected from them.?..and across the board?...perhaps some are older and have more abilities than others.....I mean we can pick up their voices on EVP....but we don't know who or what they are with any degree of certainty
but back to the original post from the OP and the question is there a danger factor?.....my two cents on that question is that it would seem that there are elements with less than benevolent intentions out there that like to hijack / infiltrate a persons perceptions.....it's not something many might want to talk about....but there's still a trail of accounts of similar circumstances out there.....here's a few more... ( I have many more)
http://www.truthspoonforum.com/t279-...spirit-contact
https://www.goodnightjournal.com/2016/06/20/paranoia-4/
Its something that should be considered when taking up this pursuit I feel.
Take Care