Howdy there Raven. I had the same problem with mine also. It sounds like you have looked at it already. If you are absolutely positive that there is not blockages in the tubing, there is a couple of other possibilites causing the prob. There is a piston solenoid that is switched to open the valve for it to come through either the attachment or the main bottom unit. It might be stuck only letting it through the attachment. Another possibility is that the main finger switch is bad, which can happen at anytime even being used only a couple of times. I would really look to make sure that water is not clogged those tubes though. By the way, that solenoid I am referring to is the small cylinder that has the white,black and green wires coming out of it. That is at least what my model has which sounds like yours. Hopefully that helps even though there can be other items also. :)
musky
May 2010