Okay this is driving me up the WALL. I just played Quest for Glory 1-3 over the last week and transferred my character into Shadows of Darkness on what must be my 3rd, 4th, or 5th playthrough. This is the Anthology version with the CD version of IV. GUESS WHAT? Garbled, skippy-speech, just like every other Sierra TALKIE game I have tested on this system. Every Sierra CD TALKIE game, thus far, has had the same exact core issue and each one handle the core issue differently (lock ups or not.) John Rhys-Davies talks normally for one moment, and then garbled-skippy speech the next. This game does support Windows Sound System, so since I am using an OPTi, I tried that. The game is playable, but the speech has a popping/crackling/static sound to it as if a record is scratched or a speaker has a hole in it. Also, the choosing "Thunderboard" trick which fixes KQ6 and almost fixes Gabriel Knight (most speech works, but there are random glitches,) DOES NOT work to fix QG4. Speech is still garbled.
ONLY SIERRA TALKIES are affected. Veil of Darkness with a patch for allowing sound effects plus midi w/digitized speech works. Hell, EVERY other game tested works with this particular 486. ONLY Sierra talkies (KQ6/GK1/QFG4 tested) does this utterly stupid speech thing. I have tried:
Changing the IRQ of the sound card
Increasing buffers/removing buffers via the mscdex parameters
Switching from a quad speed cdrom to some form of much faster DVD-rom drive
Using an AWE32, an OPTi SB Pro card in both SB PRo mode and Windows Sound System Mode in the same system (but obviously installed and tested separately)
Using Moslo (I know it shouldn't be necessary on a 486, but I need to eliminate all possibilities)
Disabling external cache in the BIOS
I have played these games on multiple systems over the years from a 486SX to Pentium I, II, and III's, and DOSBox on various modern systems. Only THIS particular, SIS-based, Tomato 4dps board are these extremely particular issues present. Only Sierra CD-talkies. What the hell. I don't know what else to try. I was wondering if there is a bad capacitor or something, but I doubt it because every other game works. Midi, speech, sound effects, CD audio - no issues with any other game. I just tested Day of the Tentacle cd-talkie edition, and it is accessing the cdrom drive and playing midi music, and sound blaster effects/speech with no problems.
It has to be this motherboard - this accursed SIS chipset... SIS and Sierra must not be able to mix...