SHOUTcast won’t support SSL so use Stunnel with free certificate from Let’s Encrypt certbot. https://certbot.eff.org/
# apt install stunnel certbot
# certbot certonly --standalone
Configure stunnel
# nano /etc/stunnel/stunnel.conf
8000 is SHOUTcast HTTP port
[shoutcast]
accept=443
connect=8000
cert = /etc/letsencrypt/live/radio.domain.com/fullchain.pem
key = /etc/letsencrypt/live/radio.domain.com/privkey.pem
Run stunnel
# stunnel
Set Auto-Renew certbot SSL
# crontab -e
15 3 * * * certbot renew --pre-hook "killall stunnel" --post-hook "stunnel" -q