I have noticed on my finished projects,digital video,the mp3 music I have added does not sound to good.Should I convert to sound wave before I use them? It almost sounds like the sound is distorting
MP3 is not the best source to start with. Some are encoded at low bitrates and then VF will try to upsample to 48k or so. There will sometimes be some clipping or distortion.
YOu might try converting them to WAVs using another application, but your best bet is to start with a WAV or CD file. This is going to be your best final quality.