ListAPIView with JSONRenderer returns text/html

Question

Straightforward question, I am using DRF with a class-based view to serve up an API for consumption by Angular. In particular, I want to respond to a GET request with JSON data that Angular can subscribe to:

class AuditListAPIView(generics.ListAPIView):
    queryset = Audit.objects.all()
    serializer_class = AuditSerializer
    filter_backends = (filters.DjangoFilterBackend,)
    filterset_class = AuditFilter
    renderer_classes = (JSONRenderer,)

The problem is that the content type for the response is "text/html" instead of "application/json". For example:

> curl -s -I <host>:8000 | grep "^Content-Type:"
Content-Type: text/html

Can anyone explain why this is so, and how to address this?