There have been many reports of unexplained humming sounds over the years both from individuals and from communities where several people heard a noise they did not understand.

As a child from around the age of eight and right up until I was 19, I went through a seemingly random series of incidents that didn't frighten me but gave me a personal mystery that I was unable to solve, and was unable to share with my family because they were unable to experience it for themselves.

I used to wake up in the early hours of the morning, usually between 2 and 3 am because there was a very loud humming or droning noise. I was always amazed that no one else in the house, or as far as I could tell amongst the neighbours, had also been woken up by it. Loud as it was I was never able to find out where it was coming from. It reminded me of the sound of a cricket that you think is in a particular place but as you move towards it you realise you can still hear it and it is somewhere else.

It sounded like some huge machine making a droning and humming sound like a giant motor.

I used to go out on the landing and in the bathroom to see if I could find where the noise was coming from. I used to look out my bedroom window on to the street outside and once I remember something really weird had happened because the normal road had been replaced with an old-fashioned one with cobblestones.

It was like a time-slip but didn't explain where the humming was from. That was I wanted to know.

I realise that some of my experiences may have been alien abduction incidents with a lot of the details blotted from my memory. I know that sometimes I was unable to move when I woke up and heard the humming. I also know I sometimes had voices talking to me but cannot remember what was said.

I know that often I would feel frustrated and mystified by the experience and not knowing what else to do would wake up my parents and sister but they could never hear anything and used to be annoyed with me waking them up about nothing as far as they were concerned.

My mother used to say I was having nightmares but that made no sense to me because I was fully awake. It was frustrating not being able to share the experience with someone who also knew what I was talking about.

The only time someone else heard the humming in my company was the last time it happened. I was 19 and living at the time in a squat in Charrington Street, Camden Town in London where I had gone looking for a girl I had met at the Windsor Festival.

The squat was very run-down and said to be haunted and I once encountered a "cold spot" there in the company of my friend Steve Whitworth, who also came from Cardiff, and who had hitched up to London with me.

Steve who woke up one night because he could hear the loud humming. Everyone else in the house slept on. Steve called across the room to ask me if I could hear what he was hearing.

I answered that yes, I could, but didn't know what it was apart from it was something that I had heard lots of times in Cardiff. It felt like a great relief to finally be able to share the experience with someone else who could hear it as well.

It was never to return and it seems that having someone else there that also heard it somehow lifted the spell. Some years later though I met a spiritualist at a college I was attending and was talking to him about it.

The spiritualist said he thought I had tuned into the "prana" and the sound of the universe. He asked if I had been chanting any mantras. Obviously as a little boy I hadn't, not even knowing what a mantra was, but that last time in London, both Steve and me had been chanting the mantra Om mani padme hum in the afternoon.

This is the mantra of the Tibetan Buddhist bodhisattva Chenrezig and is said to mean: "Hail the jewel in the lotus."

I know from the time that my friend Steve heard it at exactly the same time as me that it was not some form of hallucination or anything to do with sleep paralysis. It was also defintely not a case of tinnitus.

Moving on some more years, and I had befriended an author by name of Vee Van Dam. Vee had a series of books, including Starcraft, published by Skoob Publications about astral projection and where you can travel to and what sort of beings you can encounter in out of the body experiences, which s/he had been having since a child.

I used "s/he" because Vee believes "hirself" to be an androgynous being and part of a galactic spirit. Vee had been working with the late Robert Anton Wilson and Timothy Leary on constructing a new androgynous vocabulary.

Anyway, talking to Vee about my humming sound experiences, s/he said that "Experiencing humming sounds, of which there are various kinds, is not unusual. Often they represent pre-initiation adjustments being made to certain parts of our etheric sheath, and/or to actual Chakric points, unfolding petals which are a bit blocked or sluggish, etc."

My friend and fellow hubber, CJ Stone, quoted Vee and reported this in his book The Last of the Hippies in the chapter "Huna Druzz or Another Failed Love Quest , an Apple and a Cup of Coffee." For some reason Chris got the name of the phenomenon wrong though calling it "Huna" not "Humma."

There is a website about hummadruz at http://www.northernearth.co.uk/permhum.htm

In the late '70s I had a column in Crystal Hogben's Magic Saucer magazine, which was intended as UFO publication for younger people but had a lot of adult readers and contributors. One of these was Jenny Randles, who is a well known author and researcher.

I wrote to Jenny once to ask her about my experiences and it was she that gave me the term hummadruz, which she said was thought to be a "psychic training exercise" and had been known about since Victorian times. The term comes from "hum" and "drone" and "buzz" all combined.

I still don't really know what the source of the hummadruz I experienced was or why it stopped. CJ thinks it was my alien friends trying to get in touch with me but eventually they gave up.