I have a Orbi RBR50. Also upgraded to Altice modem through optimum

How close to the tv are you? There can be some RF bleedover from the RBR50 so if you're close to the tv or if your coax barrel connectors aren't very good you can get interference. This can also happen with cheap/crappy coax cables. Try moving your router further away. 

What FW is currently loaded?

What is the size of your home? Sq Ft?
What is the distance between the router and satellite(s)? 30 feet is recommended in between them to begin with depending upon building materials when wirelessly connected.

What channels are you using? Auto? Try setting manual channel 1, 6 or 11 on 2.4Ghz and any unused channel on 5Ghz.
Any Wifi Neighbors near by? If so, how many?

Try enabling Beamforming and MIMO. Under Advanced Tab/Advanced Settings/Wireless Settings

Modem Combo Units:
This would be a double NAT condition which isn't recommended. Couple of options,
1. Configure the modem for transparent bridge mode. Then use the Orbi router in router mode. You'll need to contact the ISP for help and information in regards to the modem being bridged correctly.
2. If you can't bridge the modem, disable ALL wifi radios on the modem, configure the modems DMZ or IP Pass-Through for the IP address the Orbi router gets from the modem. Then you can use the Orbi router in Router mode.
3. Or disable all wifi radios on the modem and connect the Orbi router to the modem, configure AP mode on the Orbi router.

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mbod wrote:

I have optimum Altice service using an Arris TM822G modem.  When I turn on the Orbi my television starts to pixelate.

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