when a dialog starts with an npc the first line is voice acted but then when i press continue or choose an answer the following phrases are all silent
help anyone?

This is actually normal, most lines in the BG series aren't voiced. Often, only the start of a conversation has VA. Party members tend to have more voiced lines but even then I'm almost 100% sure that they aren't fully voiced. (It's been a while though, could be wrong)

Right you are. I tend to hear their voices in my head after hearing the first few lines anyway. Does that make me crazy? ;)

(Besides there is no way the entire game could be voiced, with the huge amount of text and alternate paths and character classes...)