i downloaded 50 songs .. burned then to cd as mp3 files.

plays fine in bedroom with mp3 player.
but in car mp3 player it clips and makes poping sound on some of the songs.
friend says i didnt defrag my collection before moving the files or something simular.

anyone have this problem ?

Did you try turning the volume of your mp3 player up high to see if there's a problem? Sounds to me like a deficiency in your car player or speakers. Turn the equaliser down & see if it still has that effect. It might be a super bass line that your speakers can't handle when put thru the equaliser. But then again, clipping is usually a recorded peak that's too high. Normalising the songs as a whole might fix it. It depends where the problem lies. Do you have a player where you can see the volume levels? A software player or editor would be good for checking to see if the levels are too high. If you don't have one, get http://audacity.sourceforge.net/windows.php which is free. It can also open mp3's, etc. And you can open a file from an audio cd.

I don't know about windows, but on a mac, you can get a selection of songs together you want to put to CD, open them together with Jam, then normalise as an overall album. Else save it as a Jam disk image, then open with a program like Peak & normalise the entire amount to the level of your preference such as 80 or 90% of maximum (of safe level.) Then save, open with Toast & burn.