HMM now wouldn't this be helpful :
how is that 3rd party? its original ttd music (probably you already have it)
Exactly. And OpenTTD is not TTD. Do you own the rights to distribute the game? Did you buy that from Chris Sawyer? Or in this case from the composer(s) and performer(s)? Otherwise any distribution of their content is plain that: a copyright violation which you became liable of and which we would become liable of as well, if we allow that violation to persist. Your thoughtless behaviour thus not only puts you into risk to receive a cease and desist order but also us who take care about the game and these forums.