Can't set QOS markings on Mac OS Majave with the IP_TOS socket option using setsockopt

"Type of service" is defined as the second byte in the IPv4 header. Trying to set this byte in our outbound UDP traffic on our Mac OS app. Every example I have seen so far uses setsockopt for this

            int tos = 0x60;
            unsigned int tos_len =sizeof(tos);
            int sockopt_return = setsockopt(pMediaSocket->socket, IPPROTO_IP, IP_TOS, &tos, tos_len);

sockopt_return comes back as zero indicating no error, however every outbound packet has this byte set to 0x00. How do I set this Byte?

Does this no longer work on Mac OS? I am using Majave 10.14.6 if it makes any difference