Just installed OPNsense and having a few problems

[road hazard]

If somebody can help me with the following problems, I'd really appreciate it and will make a donation to the project!

I  have OPNsense 21.1.7_1-amd64 running on a Dell PowerEdge server. Clean install, updated it and added one NAT rule for Plex and so far so good!

Here's the problem:

I have an app on my Android TV (and Shield) called 'SmartTubeNext'. Since putting all my devices behind OPNsense, this app no longer works. It loads but doesn't display any thumbnails for YouTube videos.

Now, I could probably figure out what rule needs added but I'm having problems locating a place to go where I can see a log file that shows incoming traffic to the IP of the device I'm using. I looked at the log files in the firewall section but they don't show the destination IP of my internal device (192.168.x.x)....just the public IP as the destination.

Bonus question: I installed Sensei (layer 3) and with that, I can probably ditch my Pi-Hole for blocking ads, right?

[road hazard]

Well something weird happened..... after installing Sensei, the SmartTube app problem disappeared BUT........ I noticed something else.

The PC I'm using (we'll call it.... A) is plugged into an ASUS AX86U router (which is in AccessPoint mode) and a cable goes from that router into a switch. I have another PC (call it B) plugged plugged directly into that same switch.

Surfing from PC A is VERY SLOW compared to B and when trying to open the page to access the web GUI for the ASUS router from PC A, I sometimes get an error that the page can't be loaded. I wait a few seconds and it works. Also, browsing my SMB share from PC A is slow and will sometimes fail.

Tomorrow, I'm going to hard wire PC A into the switch, bypassing the router that's in AP mode.

Any ideas?