Character voices have pops and crackles. Could someone help me to correct this ?

Solution worked great, thanks!

_Zenger_'s solution worked for me as well. Thanks very much!

With that i get error in begin and lost all the sounds

What error?

Probably that that driver doesn't exist. DRV files in GOG install:
VESA
MIDNONE
DACBLAST
DACMSSYS
DACPRO
DACPRO8
DACPRO16
DACRRA

That would explain it.

This completely solved my problem. Before it sounded like a deep crackly base sound but now its crystal clear! :-) (running a SB X-Fi on Win7 32bit)

None of the above solved MY sound problems !
I'm on a Asus - m2n-sli deluxe board with an HD sound chip.
Error message = Drivers not found.
When i change it all back the sound in this game is terrible.
So what to do next ?
Also the proposed wide-screen solution didn't work either.
I've got a Full HD screen with 1920x1080 resolution.
EDIT...
OK, so i deleted the full content of the Dosbox.cfg and replaced it with the small cfg file from " Collector ".
Works better, but the sound is choppy aswell is the video.
Poor video and sound remains.

Check this thread - one of the last posts from Collector.

Hello collector. thanks so much for your input on the gk sound issues.
i am "soundprob", who was trying to figure out how to improve the gk 1 sound.
once i read your post about the crappy sierra soundblaster drivers, a whole flood of bad adventure gaming memories came back to me!
the worst of which is quest for glory 4.
i NEVER could get past like the second or third screen in that game without getting a game breaking error!
i don't think it was helped by changing the sound though.
do you have any advice for that game?
i have the version that i purchased with the quest for glory collection at babbage's in like 1997 or something.
i have looked around on the web for patches, and found qfgs.net, and i see some patches that may or may not have been there the last time i tried to play it.
what is your recommendation on the best course of QFG4 action?

If you check this website , you find a lot of useful information :)

I have new installers for most of the Sierra games. These installers automatically setup the games to run in DOSBox from a Windows shortcut, much like the GOG games, except that you must already own the games. All that is needed is to insert the CD in the drive and run the new installer. For floppy games, just copy the contents of the disks to the same folder as the new installer before you run the installer. They apply all relevant patches, both official and fan made. Each game will be correctly configured to optimal settings, both for DOSBox and for the games themselves. They include high res icons for Vista/Win7 and a configuration utility to easily change a few basic DOSBox settings to personal tastes, such as full screen or window size. When you uninstall a game, it will give you the opportunity to save your save games. Also, the installers for the DOS games only makes a registry for the uninstaller and write no system files, except for the Start Menu. I know that some of this sounds like what GOG does, but I have been doing it longer and I have been fixing Sierra games for far longer.
The installer for the QfG Collection Series can be found here.