Sound Quality and Verizon FIOS Fibre Optic Internet

Elliott, thanks for sharing. The question always is, could it sound better? 

1. Verizon wall panel
2. coax from wall panel to router with wall wart transformer power.
This is where all the noise happens. I forgot about the Verizon wall panel, so there's possibly some EMI added to the mix.

I believe you can benefit from dumping the router's wall-wart and adding an LPS. There are some good units in the $200 range. Removing SMPS power supplies really does improve SQ.

The Verizon router and Fios feed to the house is full of noise in the form of RFI and who knows what else. I tested the RF levels with a RFI meter and beginning at the entry point to my house, my "RF sniffer" was off the scale. Next, moving to the coax line then the router, both indicated peak levels of RFI. Even my ethernet cable from router to streamer was full of RFI.

My solution was to plug my router into a BrickWall power conditioner with RFI/EMI protection. Now the meter indicated zero RFI at the router and my streamer. The coax leading to the router still indicated very high levels.

The result was a very audible improvement in SQ from streaming music. The noise floor had been lowered significantly. There was an improvement in both WIFI and ethernet.

It should also be noted that these routers use a SMPS wall-wart which will introduce noise from the mains and from the device they are powering. Adding a LPS to power the router will improve performance. Many members have reported their results on the forum.

Elliott, BTW, I'm using the Brickwall because it was a spare and just sitting in my closet. 
Two recommendations:
1. Any passive power conditioner with good RFI/EMI reduction will help the router. Also, the router will no longer be using the cheap wall-wart for power.

2. Do not have your modem/router plugged into any of the circuits that your audio system uses. Don't let the noise contaminate your audio through the AC.

you are saying that the clearly better sound quality streamed from my LTE network as opposed to the Frontier / Arris router / FIOS is because of RFI / EMI? It does sound plausible.

That's my take on your situation. Fios is bringing so much noise into the house. It's possible the Fios wall control unit may use some type of noise reduction, but the RFI produced by the router is so high. 
I'm not a tech who knows about broadband, but it's plausible LTE is a cleaner signal.

AK, what DAC are you using?
What does your system consist of?

Very nice system.

Switching from the stream run over WiFi then over T-Mobile LTE there is an instant improvement in resolution and absolute clarity

Just so I'm clear on this, iPhone uses Wifi from the Verizon router. Macbook is using T-Mobile 4G LTE. 
Do both use the same DAC?

Tidal streams from both the iPhone and the Mac? Is this correct?
If so, maybe the Mac handles the stream differently.

Can you swap devices?  Will the Mac work on WIFI and can the iPhone use T-Mobile?