I was hoping that maybe the o-ring for the cap was bad, but that's not it. It's the secondary drain line. It's actually a 2003 model, not a 2008. I bought the house with hot tub already there. When I turn the jets on, the leak is worse, so I'm guessing the drain line must be under some pressure. I called the tech and he's coming out to take a look. He was all gloom and doom, saying that the plumbing lines are surrounded by foam and have to be chipped out to get access to them, even if it's a small leak. Sounds like lots of $$$.