Dropdown menu is under the slider

If your menu doesn't have z-indexes set, or they are not large enough, the slider will be placed above your dropdown or fixed menu, as the "moving" HTML elements, or the ones that has some JavaScript codes in them, usually get a higher z-index by default, than the non-moving elements.

If you put this code into your theme's/template's css file, it will solve this issue:

.n2-ss-align{
     position: relative;
     z-index: 0;
}