This is the first time I'd come across this in 40 years of studying the subject. I have heard of EVP, which is the vocal recording of the spirit voice. It would be interesting to see what the Psychic Research Society thinks of it.
When I was taught many years ago, it was to think of any logical reason the phenomena happened first, so for this one would have to make sure the tapes etc hadn't been used before and as such could have action on them already etc. Due to the amount of fake stuff going on, we must always keep that in mind.
I have known many pets to come through during Mediumship messages, always bringing joy, love and a spring in their step.
For those who wish to read more about pets in the Spirit world, the best book I've read is pretty old now, but is called When Your Animal Dies by Sylvia Barbanell, the wife of the famous medium who brought through Red Clouds teachings.
http://www.amazon.co.uk/When-Your-Animal-Sylvia-Barbanell/dp/085384111X/ref=sr_1_1?s=digital-text&ie=UTF8&qid=1450171454&sr=8-1&keywords=barbanell+sylviaAs a side note, Spiritual Animal Healing has also started to become more common, with Margrit Coates
http://www.theanimalhealer.com/I must admit my pets love a dose of pet healing.
