Spotty WiFi and no internet on Ethernet

• Model: Formuler GTV
• Retail Box or Provider Box: Retail Box (Amazon)
• Firmware version: TunerService 10.0.32 / Firmware 10.0.31
• MYTVOnline 2 version: 10.0.31-5514-c3bf1f1f4
  
• Connection with provider: M3U playlist
• Box connected with: WiFi (primarily)
• Did you factory reset your device? and when?: multiple times during troubleshooting
• Picture url (only https): N/A
• Video download url (only https): N/A
• What issue(s) are you having? No internet when connected via Ethernet
• What was were you expecting to happen? I expected a connection on Ethernet
• What happened instead?  
  • I get good link lights at whatever switch I plug into
  • System says "connected" with an appropriate IP address
  • After trying to sign in (or any app requiring internet access), system informs me there is no internet, and refuses to connect
• How can we reproduce the issue you are having? I'm as baffled as you are at this point; I'm not sure
• What have you tried if anything to rectify the issue?
  • Updated system software out of the box
  • Turned off IPV6
  • Tried Private DNS through cloudflare (Network -> Advanced -> Private DNS -> select 1.1.1.1)
  • Tried Private DNS 'off'
  • Tried Private DNS 'automatic'
  • Tried static IP configuration on both WiFi and Ethernet (specifying blank, google, cloudflare, and local DNS)
  • Disabled internal network BlockList

• My Network
  
  • Verizon FiOS Gigabit
  • Router: higher-end Protectli running OPNSense 22.7+Unbound DNS
  • WiFi: 3x Eero pro wifi in bridge mode, all 3 connected via ethernet to router
  • 80+ other devices connected via Wifi & Ethernet with no internet access problems

What I'm really struggling to understand is why the GTV "finds the internet" on Wifi, but not on Ethernet. Since my Wifi is bridged, the GTV gets the same [DHCP] configuration on either interface (or, it should).

When I was messing around with it last night, I also noticed that the GTV would randomly switch from one of my excellent-strength APs to one with poor strength, then immediately switch back. This interrupted service, and even when connected to the excellent-strength AP, the connection wasn't solid (sometimes dropping out every 1-2 minutes with an exclamation mark before reconnecting). Trying to configure a static IP on Wifi (as I've read in the forums) resulted in the same "no internet" symptoms as Ethernet has.

Ideally, I get Ethernet working, and forget about Wifi unless I'm traveling.

I have also read bits regarding the "internal interntet checking" mechanism of the box, but without further details I cannot create additional firewall rules to allow those checks to complete. And since every other device on my network doesn't have problems, I'm not sure where to start, either. In my experience these types of "internet checks" are commonly fixed with DNS, but I seem to have exhausted all DNS options available to me via AndroidTV. Maybe I'm missing something?

Quote from SAM

Settings -> Network Internet -> Wifi OFF -> IP - > click on dhcp.

Already tried this ... no internet on Ethernet. Even switching from static to DHCP with Wifi off.

Strangely, I receive a notification that "Ethernet is not connected" with an exclamation point, but if I look at Settings -> Network & Internet it clearly says "Ethernet connected" with a valid IP address. Trying to reconnect MOL2 to my provider hangs at 10% connecting, and eventually errors out with "Error Please check your internet connection, portal URL, User ID, and Password ... Code 7." Settings -> Network & Internet still shows an Ethernet connection, and I still have a notification stating otherwise.

Quote from Robbo

Have you tried connecting the formuler box via ethernet directly to your router? That’s a test I would do.

I've tried direct to router, and also different switches within the network. Router still hands out the correct DHCP information; but Formuler can't seem to find the internet.

Returned original formuler; received new formuler. Exact same problem. No internet over ethernet. Direct to ONT, direct to router, nothing works.