With SHUFFLE on, songs with similar/same titles will play back to back

Songs with similar (or the same) titles play back to back in shuffle mode. For example, if "Round & Round" plays, the next song will be "Roundabout". I have multiple copies of the song "Aqualung" on my IPOD and once one plays, they then all play one after the other, This CAN'T be a coincidence and I am not seeing a pattern where one does not exist. Note that they are NOT in a playlist. How do I stop this?