The cipher suite settings appear to be here
ssl_ciphers ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES256-SHA;
So, I have tried to put in TLS-DHE-RSA-WITH-AES-256-CBC-SHA but I’ve run out of disk space so can’t commit the changes. 