All of the “snooping” is self contained. You run the network controller either locally on a PC, or on one of their dedicated pieces of hardware (dream machine/cloud key).

All of the devices connect directly to your network controller, no cloud connections. You can have devices outside of your network connected to your network controller (layer 3 adoption), but that requires port forwarding so again it is a direct connection to you.

You can enable cloud access to your network controller’s admin interface which appears to be some sort of reverse tunnel (no port forwarding needed), but it is not required. It does come in handy though.

As far as what “snooping” there is, there is basic client tracking (what IP/mac/hostnames) to show what is connected to your network. The firewall can track basics like bandwidth/throughout, and you can enable deep packet inspection which classifies internet destinations (streaming/Amazon/Netflix sort of categories). I don’t think that classification reaches out to the internet but that probably needs to be confirmed.

All of their devices have an SSH service which you can login to and you have pretty wide access to look around the system. Who knows what the binaries are doing though.

I know some of their WISP (AirMAX) hardware for long distance links has automatic crash reporting built in which is opt out. There is a pop up to let you know when you first login. No mention of that on the normal Unifi hardware, but they might have it running in the background.

I really like their APs and having your entire network in the network controller is really nice for visibility but my preference is to build my own firewall that I have more control over and then Unifi APs for wireless. If I were concerned about the APs giving out data, I know I could cut that off at the firewall easily.

A lot of the Unifi APs can have OpenWRT flashed on them, but the latest Wifi7 APs might be too locked down.

I assume you are powering the dock? Many docks require external power before they will pass video.

Does the screen on the deck shut off or stay active?

If the screen stays active that means that it isn’t detecting an HDMI signal through the dock at all.

If the screen shuts off but you get no video through the receiver, you should try hitting the power button one to shut it off wait a few seconds then turn it back on (while plugged in). Even the official dock has issues getting the deck to switch to the external output but putting the deck to sleep and back on gets it sorted out.

If that still doesn’t do it plug in directly to your TV to narrow down the problem (removes the receiver as a variable). Next try a different HDMI cable, and as a last resort try a different dock. If you know someone else with their own deck you can try theirs to eliminate a hardware failure on your deck.

Slows down then freezes sure sounds like an out of memory situation, so to add to yours here they might actually want less swap. Sometimes you would rather hit the oom killer sooner instead of waiting on swap to fill.

Ideally login via SSH from another machine to figure out what is using the memory (hopefully the system is responsive enough for SSH), and if it is your critical programs causing the problem then you should consider a memory upgrade.