I've been trying to astral project for a little while now, with no success. I've been using a visualization technique from Astral Projection by John Magnus where you visualize while falling asleep and project the next morning.

I've been probing the hypnagogic state and I keep getting awakened by strange bleeps bloops and zings. This happens about 3-4 nights a week, more frequently if I'm more tired. It sounds like cartoon/computer noises most of the time, there's a springy "boing" sound that I hear often, and once it was a bear/cougar growl.
These noises wouldn't be a problem at all but when I hear them I get a sort of targeted electrical jolt feeling, and my muscles flex in the area of the shock. After I get the shock I am wide awake, and when I try to fall back asleep I get another sound and shock about half the time.

I've been experiencing this for a long time before I started trying to astral project, it just happens much more now.
I used to think that the shock was the consciousness snapping back to the physical body from the astral body, but I'm not sure.

So I was wondering what are these noises and how can I stop them? They can get pretty annoying