Audio not working on iBook G3/600 14.1, but it occasionally chimes when booting.

[Gabryx86_64]

I recently got a second hand iBoom G3/600 14,1" (PowerBook4,2), and since I got it audio in OSX doesn't work, and it chimes less than one time out of ten.
This happened both when it had the already installed 10.2.8, then now that I installed 10.4.

 

[Gabryx86_64]

Now that I think about it, the chime only happened when the battery was completely drained and I plugged it in and started the iBook.