I've been having this issue with sky q and starlink - my sky box is plugged in to a managed switch via ethernet, which then bounces to our primary router/firewall. This then uses a WAN connection to connect to my neighbours router (ethernet again) and we share the starlink (which is connected via ethernet to my neighbours router).
Not sure why the latency would be an issue - every connection I have is through super fast gigabit ethernet, and the starlink is very low latency. I concluded the latency discussion is a red herring here - mostly because conditions on the web backbone routers can sometimes cause latencies to go through the roof whether you have a fat fibre pipe or not (for histories sake, do a google search for black hole routing negotiation in internet design - routers on the internet are designed to route around broken nodes, and this usually involves a spike in latencies and packet loss).
So I figured it had to be the DNS. My router has its DNS default to Googles servers, as they tend to be reliable.
The Sky Q connection however, whether it be ethernet to your router, or the built in (and frankly terrible) wifi the sky box uses will have a DNS server default that is pointing to what I assume is skys own DNS server (mine was 162.252.172.57). These servers are vital to any communication on the Internet, as routers don't understand our language centric names for servers - they use numbers. In order to get these numbers, they need to consult a DNS server lookup table., and preferably one that as complete as possible as quickly as possible (anyone who has set up a web servers DNS entry will know it takes some time for the record to propagate over the Internet- typically up to an hour, which tells you not all DNS servers are created equal). DNS server interrogation will generally have far bigger waiting time than connection latency, especially if the one you are using has to point you at another node because it doesn't have the info requested - far easier to just go to the fastest and most regularly updated to begin with.
So, changing the DNS setting on your sky q box:
1) Work out which DNS server is likely to work best - googles are good (8.8.8.8, and 8.8.4.4), but if you want super quick, cloudflare and WARP have set up a faster one (it's at 1.1.1.1 - if you type that into your browser, it takes you to their page where all is explained).
2) On your sky q box remote, hit the home button, and scroll down to "settings". Press "OK" twice on the remote, then scroll down 1 item to the "Network connection", and select the "Network setup" button. Select "Advanced settings", and then "set manually".
3) You'll now have a page with headings of "IP address", "Subnet mask", "Router", and "DNS server". All of these will be set, as the auto config uses your routers DHCP, so you can ignore the first 3 (although taking a photo of all the settings can only be useful, so do that with your phone, or write the info down).
Drop the selection box down to the first box of "DNS server"(it will go black, and you won't be able to see the numbers as you enter them - not sure why sky decided this should happen), but if you press the number 1, and then the right arrow on the remote, it will enter it into the 1st box, and move to the next. If you.have another address you need to enter, just hit the numbers for each octet (the numbers separated by the dots).
Here is how mine looks when done
Hit the confirm button, and it will give you a list of your manual IP settings like this
For no sane reason the DNS isn't listed but will be in the edit page.
4) Exit the menus, and then check the network setup page to confirm you are all connected.
5) I'd recommend you set your sky box with a fixed IP address in your router - you'll need to consult your router manual for this, as they all use different means. The reason for this is so the routers DHCP server doesn't assign the fixed IP address you are using while your sky q box is off (you can also set your router DHCP address range so ot leaves unassignable addresses, and then set the IP of your sky q to one of these addresses).
6) If you find you have an address conflict when you turn the box on due to something else having been assigned the box's IP address, reboot your router while the box is on, and it should clear.
As an aside, if you change your connection back to automatic, the software on the box will rewrite the old DNS address in place of what we've just set, so you'll have to go set it again (back to square 1.....)
My box has been running beautifully since doing this - just downloaded an hour long program in about 30.seconds flat, and all the thumbnails etc load swiftly (but more importantly, my box now no longer tells me it has no Internet connection all the time,so swearing over 😄 ).