A:
Pink,
This is likely happening because your audio is being sent out externally, rather than using the television's internal speakers. If you assign the audio to the TV speakers, the equalizer option will appear available and you can adjust the options there.
If you send your audio to a receiver or Home Theater system, the equalizer options should be on those devices. So as not to interfere with the raw audio signal, it passes it through so that the receiver or Home Theater system can equalize or assign a sound pre-set to the audio track.
Thanks for your interest in Samsung products.
--Mr. S