So I finally got to the remaining where destiny islands is and I triggered the cutscene where you go into the hole and Ansem starts talking before Sod Riku appears in front of you. Thing is there's no voices, so I thought ok I think that might be normal, until i got to the part where sod Riku turns into ansem and there are still no voices. Has anybody encountered this bug before? Or is there an audio option that I accidently turned off

It was probably a problem with the audio.  I remember that one time, while I was playing Re:Chain Of Memories, the audio suddenly muted itself.  At first, I thought that I had pressed the mute button on my remote by accident, but then I saw that it was the game, and so I turned off the PS3 then turned it on again, and it fixed itself. But it's nothing for you to worry about.

Edited November 8, 201410 yr by Shigehiko

That happens a lot to me. I use an SD cable on my PS3 (yeah yeah, old school yellow-white-red), and sometimes I have to wiggle it back in.

in the 100+ hours I've put into KH1.5 HD ReMix, I've encountered audio drops a total of 4 times... most of them took place in Neverland with Hook's ship. If you restart the game it usually comes back on. Its not really that common overall but I know what you are talking about.