Poor loading time

I have a domain registered with Cloudflare. The second level domain points to a site hosted at Firebase. It works fine.

A subdomain points at my home NAS via an A record. The load time when I go through The A record at cloudflare is terrible. When I go to the same nas through a DDNS provider (noip.com) it is really fast. So I’m assuming that I need to change some settings on Cloudflare?

In fact, some elements don’t seem to load at all going through Cloudflare.

Both the second level domain and the subdomain are proxied image .

I have a certificate installed on the NAS for the DDNS provider. The subdomain on Cloudflare has a valid cert.