Why do some DVD that you burned play OK on the computer, but
On the DVD player some parts breakup or you have sound distortions.
Not all, just some. Is it from the source or the burning process?
Isn't there software that could screen the DVD
Before you burn it for irregularities

I've found that DVD Players are picky about the media they will read from. Certain brands of DVD media will simply just not play on some brands of DVD player. It's best to find abrand that works, and then stick with it.

In my own case - I've found that Maxell DVD's almost always work in my Sony DVD player, but other brands either give me trouble or otherwise aren't readable by the player at all.

You might want to try another format as well. My Dvd player is allergic to DVD+R Media but everything on DVD-R will work just fine. You also can try burning at a lower pace try doing the same thing you did before just don't burn them at full speed use 1.5x or 2x (I know its anoyingly slow but just humor me). As philly said the brand is importend as well I ussually go for Sony product after using Memorex before and ran into some trouble. Another thing is Double Layer DVD's, they give you more capacity but are not ideal for Videos especially if you have an older DVD Player. If you have the source as a file on your computer and it plays fine there you can rule out a source problem, but if you do some conversion to the files it could cause sound distortions and problems with audio/video sync.

Just to chime in, I stay away from Memorex.

I have a Toshiba SD4980 that plays just about any brand of media, but Memorex... ehh. Even the cheap bulk no-name ones work well.

IMO, I find the + works the best. (i.e. DVD+R, CD+R, etc.)