Can't chromecast streaming services on T-mobile Home Internet

I'm having no luck either. It was working when I first got the service. Now nothing. I'm getting closer to cancelling this service. Not exactly sure what tmobile expects, but if I really can't watch anything, there's no point 

I've spent multiple hours on the phone with tmobile, and google. (The first time it took them 6 hours to call me back because I lost my place in line) I can't get any of my google smart home devices to work with the tmobile modem/router. I factory reset 5 google home devices and reset them up with a mobile hotspot instead of the tmobile internet(suggested by google to troubleshoot) They had no issues and worked fine. After factory resetting those same devices they will not work with T-Mobile's equipment. This is the second 72 hour ticket I've had to put in for this. (The first time (over a month) I never received a call back and the issues never got fixed). If T-mobile is going to charge me for a service that I cannot fully use this is a problem. I had no issue with this issuing my own personal cable modem and router. Even T-Mobile's iPhone hotpot worked. The tmobile tech said that is new technology...but so far I'm unimpressed. Where's my compensation for the time I've wasted and a service/equipment that doesn't work properly?

Definitely not working for me either, and it's definitely the T-Mobile equipment. Needs an urgent fix.

I am having the same issue. Good thing i have not gotten rid of my other network as it works fine there. 
Have been trying to search the internet for something but so far no luck, as you said i can cast my whole screen but if i want to cast from youTube the sreen just goes black and then says it cannot connect.
This is the second issue i have had, the first was live hulu tv which will not work either (there’s a thread on that if you search)
I am going to keep digging and if I find a fix ill share it here.

Also want to say and I quote from the tmobile tech "you should be getting faster speeds, there is 5G in your area". I was only getting around a 10-15mbps download rate with a "very good" signal. 

Had 1st gen chromecast stick. Could Chromecast Disney and Amazon, but not YouTube (just balck screen then back to screensaver) or Netflix. In fact, Netflix app on my phone couldn't even load content.

Went out and bought brand new Chromecast 3rd gen with Google TV. Couldn't really get through the setup from my Home app on the phone, and had to do it on screen with the remote and on-screen keyboard. The Google TV on the Chromecast which has streaming apps, like a smart TV, works, but if I try and cast YouTube from my phone or laptop, I get exactly the same results as I had before.

I used an older wifi router to setup a separate wifi network (2.4GHz only) and connected the Chromecast and phone to that and plugged that into T-Mobile trashcan ethernet port. Worked fine, but the older router is too slow for my tastes. So it's the T-Mobile's WiFi that's the problem, not modem part.

JB814 wrote:

I've spent multiple hours on the phone with tmobile, and google. (The first time it took them 6 hours to call me back because I lost my place in line) I can't get any of my google smart home devices to work with the tmobile modem/router. I factory reset 5 google home devices and reset them up with a mobile hotspot instead of the tmobile internet(suggested by google to troubleshoot) They had no issues and worked fine. After factory resetting those same devices they will not work with T-Mobile's equipment. This is the second 72 hour ticket I've had to put in for this. (The first time (over a month) I never received a call back and the issues never got fixed). If T-mobile is going to charge me for a service that I cannot fully use this is a problem. I had no issue with this issuing my own personal cable modem and router. Even T-Mobile's iPhone hotpot worked. The tmobile tech said that is new technology...but so far I'm unimpressed. Where's my compensation for the time I've wasted and a service/equipment that doesn't work properly?

I have Chromecast with Google TV, a Nest Mini Speaker, a Home Mini Speaker, a Nest Thermostat, an Echo Dot Speaker, 3 Phillips Hue Smart Bulbs, 4 Geeni Smart Bulbs, 3 Wyze Surveillance Cameras, and 1 Wyze Lock.

Sheesh!

Everything works fine, EXCEPT my devices that have the Google Assistant attached to them. This even includes my Pixel 4 XL.

My Chromecast with Google TV will not let me use the assistant on the home screen. Because this is Google TV I'm not casting from my mobile phone. But I do appear to have connectivity issues using Hulu. Netflix and YouTube seem to stream just fine. In fact once an app has started streaming, the Google Assistant seems to work okay within the app. But for some strange reason when you go back to the Google TV home screen it loses the internet connectivity to use Google Assistant.

I'm experiencing the same problems with my two Google speakers. Every time I use the wake word, the Google Assistant will tell me that there was some type of "glitch" and to wait a few seconds and try again. 

Hey T-Mobile, there's clearly an undiscovered link between Google Assistant and the T-Mobile home internet service. All my other smart products seem to work just fine. But all my Google Assistant products cannot maintain a solid and consistent connection. I've experienced some luck with disconnecting and reconnecting the affected device, but that work around is not consistent.

I have occasionally had problems streaming YouTube, Pluto, etc. from my phone to TV. I found by switching from the 5GHz band to the 2,4GHz band seemed to help. Might be worth a try,

Anyone try switching to 2.4 with success?

Hola, 

After removing everything and resetting up my Chromecast from the google home app I was able to get it to work. I can't recall doing anything differently but i know have youTube casting from my PC again to the Chromecast with no problem.