There is a difference.
to set something right/ make something right = to make something good; put something right/ to correct something/ to alter a situation to make it more fair.
Example: This is a very unfortunate situation. I'll ask the people responsible to set this matter right.
to set it straight= to correct someone by providing accurate information or make an arrangement honest or fair.
Example: To set matters straight I'll pay you back Monday .
It is sometimes put as set the record straight , meaning "correct an inaccurate account," as in "Just to set the record straight, we actually arrived at ten"
To get it right = to be correct. Example: I want to get this problem right
get it straight= to get the truth. Example: Now let's get it straight, where were you till 3am?