Turnkey Linux lots of NTP network activity and 255.255.255.255/250 possibly causing slow LAN

I have a server with Turnkey Linux Core 18.1 installed with a standard Immich installation.

Since migrating this server from an older computer to a newer computer (copied the entire hard drive contents and then made it bootable), the local network has been slow.

I am not very knowledgable on Linux but am researching and have used IFTOP and I see I have some network activity which I don't understand and could be causing my issues.

First I see lots of constant traffic (usually tens of requests per minute) to many, various NTP servers on the NTP port.

If I stop the "ntp" service the NTP traffic stops, but I would like to know if this volume of traffic is normal and if not what I can do to fix it.

I also see constant traffic from 255.255.255.255 and 255.255.255.250. Is this normal?