Mike,
Good dissertation on how to use one of those. I don't do it that way, but who cares? The way I do it is to place the ball just behind my right little toe on the go button and push up or down. I do that cos my ankles are trashed and to do it the way the blog entry writer says is all but impossible for me to do.
Sarabela,
Take the controller housing apart and check it. It could be corroded, full of lint and debris, rusted, or the carbon disks could be broken and shorting out. I've seen all of those.
If dirty, corroded, rusted then clean it. If it needs adjustment ArcaicArcane has a great tutorial on how to adjust them.
If it's beyond that, replacing the controller is easy. I keep replacement as the last option though. Just me I guess.
Joe