I have a GBA SP that I am trying to repair because it has absolutely no sound. I tested its speaker and it works in another GBA SP. The volume is all the way up, but it still is not making any sound. The games play perfectly though and the screen works fine.

Is it possible that somehow the sound onboard is busted and I have to get another GBA SP board for it? If so, anyone have any suggestions on where to buy one? Cheap is the keyword here people.