Help Only Recognizing Some Song Files

[coondoggyjr05]

Hello, I am kind of new to this, so please bare with me. I have had the HTC hero for about a month now. I have not had any problems up until now. I could listen to any audio file no matter what program I use. But now, some of my files arent showing up. In MixZing, it says "Error opening the audio file". They are .mp3's just like the songs that actually do show up. Any ideas as to why I can only access some of my audio files?
BTW they are all put into the same file location on the sd card.

I appreciate any help.
Thanks

 

[takeshi]

Mount the SD card and see if your PC can play them to see if the files are corrupt for some reason.