If you try to play a song in Front Row on your iMac G5 (iSight) but the application can't find the song because it's not in the default iTunes library, you'll see an alert message that either says, "iTunes cannot play this song" or "Communications error." If this happens, just show Front Row where you keep your music.
If you keep all of your music in one folder location:
If your music is stored in different folder locations:
Tip: If you want to play just one song from another folder, play the song in iTunes first. Front Row will be able to find it once iTunes knows where the song is located.