Need major help with 20D

I am in Japan for 2 weeks and of course Murphy followed me here. I am having some sort of weird shutter lag with my 20D. If I push it in half way to get the focus and then push it the rest of the way it takes several seconds to fire, upwards of 5-8. However when I just fire without the half focus it fires. It happens about 65% of the time and is getting to the point where I am missing shots because of it.

The shutter release on the extended grip does not have this problem so I thought maybe the contact is dirty or mucked up on the body's release. I tried blasting it with compressed air but no luck. Does anyone know of a way to clean underneath the button?

I have resorted to taking the pics upside down using the vertical grips release but is getting annoying.

If you have any ideas please help!

Bunping this in hopes of getting some help. Probably the last day with the net for a while so I hope someone out there has some ideas.

I'm afraid you may have to take it in for a repair, seeing as the grips vertical release button works ok it sounds like the shutter release on the camera is faulty.

My 10d did this for a spell. Switch to using the back (*) button for focus and see if that changes anything.