Stuttery audio on CD and DVD playback.  Much worse on DVD. 
Independent of software player...but some players are better than others. 
Sony laptop PCG-FXA36.  
Video is fine. 
Audio is terrible.
It worked fine when I first got it. 
Nothing I have tried has fixed it and the laptop is unusable
to play DVD's. 
Hopefully the solution won't require the original disks I got with 
the machine...they are here somewhere...but it would be a hairy, lengthy
search. 
HELP!!

You will need to do some troubleshooting here. First question is:

1. Is regular audio sounds bad? Such as when you play an mp3 file? 
   If the answer is yes, then try downloading a WAVE file and playing it back. 
   If it still sounds bad -- then it is your sound card problem. Check
out http://esupport.sony.com/perl/swu-list.pl?mdl=PCGFXA36&UpdateType=Everything.
Some interesting things to note there:
    06/03/2003 Sound Patch Audio (Sound) Sound Patch - Resolves the
issue where audio stutters when played back using USB speakers.
11/20/2001 Sony UI Library System Components Updated Sony UI Library -
Resolves the issue where the SonyŽ SonicStage? application is slow
when ripping/recording ATRAC3 or WMA files from an audio CD.

VIAŽ AC'97 Audio Controller Driver Utility Audio (Sound) VIAŽ AC'97
Audio Controller Driver Utility See more..
If just mp3s sound bad but not WAV, then note it and proceed to #2.

2. Is audio in downloaded video files sound bad? You can find some
sample files here: http://www.only4gurus.com/v3/showcat.asp?Cat=Video%20files

If it sounds OK and mp3s sounded ok too, then there might be something
wrong with your DVD player. Call Sony, have them go through their
regular troubleshooting, hopefully your laptop is covered by a
warranty for replacement.

If video sounds ok, but mp3 sounded bad (and you might want to do this
step anyways ) -- you might have the issues with your audio codecs. I
would recommend uninstalling your sound card, removing everything from
control pannel -> multimedia -> sounds and reinstalling your sound
card at that point. Then reinstall your DVD player software.

Let us know if that helps!

i think that a inner wire is dis-adjusted, so the sound is stopped
little parts of time

Does it sound bad with headphones or external speakers also? This can
rule out or confirm a bad wiring connection to the internal speakers.