[Fredrik]

I decided to use the interface pro theme responsive menu but if you want to hide that when using un other plugin responsive menu you could do like this…

Go to
appearance
theme options
design options
custom css

and write the following lines where you can put any pixel value that works for you:

@media only screen and (max-width: 767px)
{
.menu-toggle {
display:none !important;
}
}