If your tv or hifi have phono inputs for left and right audio, then use a "Y" audio lead this has a headphone plug at one end for the MP3 player output and 2 phono plugs at the other end (usually red and black or white and black). These plug into the "Audio In" sockets on your tv/hifi.
Phono plugs and sockets are coaxial meaning one centre pin surrounded by a tube like shield.
It depends on what type of connection you have on both devices.
If the player have an USB connector and the TV or DVD player also have one, use it. You may need to use an USB cable.
The same goes for any conector that is common to both.
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