TR626 Low Volume, faint LCD

[SynthFellow]

Hi, i got an 626 wich is semibroken. There are sound coming from the machine but at a low volume, and the lcd-screen is very faint like it gets too little power. AND if i try to run it on batteries there is no sound at all. The little red led is lit.. but kind of blinks. Any ideas of what to do?

EDIT: Theres a difference if i change AC-adapter. To me it seems like a power issue. Could it be bad capacitors?? And in that case which ones do i try to replace at first?