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So I will check and provide a solution here.
Yes, it's possible condition is button is in html not as a image.
And if you just need direction, Go to your active theme sections/slideshow.liquid and search for that button html. And once you find it just remove or comment it.
I suggest comment it. In case in future you need it can can get it back easily.
There is another way to remove it, for that you have to use css and assign specefic class or ID of button as display:none.