well, i've been sitting with a screwdriver and a soldering iron few times next to this unit... but it would be great to hear some ideas ofcourse.
this is how it looked like first:
http://vimeo.com/3026386(all OS's including original akai acted the same way: pad's being hit automatically, randomly and very rapidly)
later the screen started to flicker or the light got clearly much darker.
what was able to do myself is that i took all boards and parts apart and checked for any visible fault in cables or connections, put it back together but the problem didn't go off.
what i'm actually thinking is that propably the motherboard is fücked and it will be cheaper to buy an used one than repairing this unit...