ePSXe help

[Carl the Llama]

well im trying to play a Lunar on my ePSXe and every time I start a game there is always something wrong with the sound, it sort of jumps every few seconds and is really irritateing to say the least, can anyone help me out? im useing Pete's OpenGL2 PSX GPU and no matter the settings I cant seem to get the game to play without the sound smurfing up, any help would be greatly appreciated.

Edit: It only seems to happen when they are talking.