Solution to Syncplay not working behind nginx reverse proxy (NPM) Unraid

Add this to advance configuration

location / {
# Proxy main Jellyfin traffic
proxy_pass http://myIP:8096;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Forwarded-Protocol $scheme;
proxy_set_header X-Forwarded-Host $http_host;
# Disable buffering when the nginx proxy gets very resource heavy upon streaming
proxy_buffering off;
}
location /socket {
# Proxy Jellyfin Websockets traffic
proxy_pass http://myIP:8096;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Forwarded-Protocol $scheme;
proxy_set_header X-Forwarded-Host $http_host;
}