Try launching the songs from within LW's library & launch them with a different player, not WMP.

Am I understanding properly - you never used to have this problem & songs played fine thru WMP & burned to disc without the end being messed up? Have you tried downloading files from different sources...same song but a different version of it from a different source than the original download (eg higher bitrate, or download from a modem source rather than cable/dsl etc)? If you have songs in your library that used to sound fine, do they still play without a problem?

You can stop sharing files from your LW library. Right click the file > stop sharing file. Or if it's a whole folder that contains the crappy songs, stop sharing that folder (tools > options > sharing). You can delete things later on, if you want to, but for now I'd stop sharing them.

The title of that thread's just referring to how later versions of BS weren't working properly & gives a link to an expired beta version of BS which works well