You should set both autoplay and autoplayTimeout properties. I used this code, and it works for me:
$('.owl-carousel').owlCarousel({
autoplay: true,
autoplayTimeout: 5000,
navigation: false,
margin: 10,
responsive: {
0: {
items: 1
},
600: {
items: 2
},
1000: {
items: 2
}
}
})