Windows Media Player 9, 10 & 11 have a built-in behavior setting where they analyze the file to transfer. If they think the audio quality can be improved by converting the MP3 file to WMA, they do so before transferring the file. You cannot change that on Windows Media Player 9 or 11 so if you really want to stop that from happening, you need to roll back to Windows Media Player 10 if you use 11 or upgrade to Windows Media Player 10 if you have version 9 (note Windows Media Player 10 needs Windows XP to run). You can get Windows Media Player 10 here http://www.microsoft.com/windows/windowsmedia/download/default.asp . the article on rolling back to Windows Media Player 10 is here http://www.normsoft.com/kb/idx/0/166/article/ .

To change this behavior in Windows Media Player 10:

1. Connect your device just as if you were about to transfer files.
2. Connect to your hotsync cable/cradle and start Pocket Tunes.
3. Open Media Player.
4. Go to the Tools menu, select Options, then click on the Devices tab. You should see your device listed.
5. Click on your device in the list, then click the Properties button.
6. In the properties window, click on the Quality tab. Uncheck the box that says "Convert files as required by this device (recommended)".
7. You may get a warning message. Just click OK to get past that, then click "Apply" if available and "OK". Back to the Options screen, click "Apply" if available, and "OK". You are back to the regular Media Player screen and you should now be able to transfer MP3 files without them being converted.