Something for the FAQ/Wiki: If you are on X64 builds and sometimes have trouble with sound cards, this will also affect some of the emulators, especially Dreamcast/Naomi. If they see no soundcard they simply go back to Emulationstation. The Libretro cores don't care, they just execute without sound. This has baffled me because I thought the .chd images were broken, but it was simply the sound setup. Please refer to my other posts about X64 sound / HDMI enumeration too see my root cause here.