How do I keep the CC from going off my Samsung 5 smart TV?

When you turn it off are you going into the setup menu to do this?? if so after it comes back on and you go back to the menu and you see it..as "on" You will need to save your settings before you exit out of the menu

There should be an option in the Setup menu for CC (closed captioning) to turn it on and off. If it's already off, you're going to need a new Main board. (You might want to try updating the software first)

There is a little button to the right of the "0" that says "CC" for closed caption. Just keep pressing it till the option "closed caption off" appears on the screen. Then, hit STATUS EXIT, and you're done.

Here's the copy on CC from my manual LC-32SB23U.

1. Press CC.
This will present the Closed Caption information display.
2. Press CC while the Closed Caption information is
still on the screen.
Press repeatedly until you select the desired closed
caption service.

INFO BOX ON THE SCREEN,
Air ANALOG
Audio : MONO
CC : 1/2 CC1 ------ Closed Caption information
Ratings : NONE

Example:
If a program has three services (Digital CC(ENG), CC1
and Text1), the closed caption display will toggle in this
sequence:
1/3 ENG -- 2/3 CC1 --- 3/3 Text1 -- Off
The CC button keeps a record of the last service
selected in its memory.
If the last closed caption mode (e.g. 1/3ENG) you
selected is not available for the next program, or on
another channel, the closed caption service that is
available is automatically selected, and this service
appears in parentheses, e.g. “1/3(CC1)”.
Closed Caption services that appear in parentheses will
not be stored in the CC button's memory as your last
selected service. Only services that you have selected
with the CC button are stored.


If this doesn't work, the TV may need a software upgrade.
I can get you a copy of my manual LC-32SB23U for you. But, are you sure there is and "A" in the middle of your model number?

on your remote go to cc push that until it sayes closed caption off not positive but pretty sure

Check the cable box to make sure the captions aren't truned on in the cable box.

If not -if it really is the Magnavox caption service- then -

This is assuming you have the original remote:
1 Press MENU to show the on-screen
menu.
2 Press VOL+ or VOL- until SET is highlighted.
3 Press CH+ or CH- repeatedly to
highlight CLOSED CAPTION.
4 Press VOL+ or VOL- to display the
CLOSED CAPTION menu.
5 Press CH+ or CH- to select the
closed caption you want (OFF, CC-1,
CC-2, or CC-MUTE). CC-MUTE sets
the TV to show closed captions when
you press MUTE. The TV volume will be
disabled until you press MUTE again to
restore the sound.
6 Press VOL+ or VOL- to confirm your
selection.
7 Press TV/AV/EXIT to remove the
menu.