Firmware Version 2.5.1.8

What is the Mfr and model# of the ISP modem the NG router is connected too?

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 RBR and RBS to begin with depending upon building materials when wirelessly connected. https://kb.netgear.com/000036466/How-far-should-I-place-my-Orbi-satellite-from-my-Orbi-router

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(MIMO may or maynot be needed) and WMM. Under Advanced Tab/Advanced Settings/Wireless Settings

Try disabling the following and see:
Armor, Circle, Daisy Chain, Fast Roaming, IPv6 and Set 20/40Mhz Coexistence to 40Mhz only. Set Short preamble instead of Long preamble modes. Save settings and reboot the router and satellite(s).

Above suggestions working:
https://community.netgear.com/t5/Orbi/Throttling-Devices-RBK53/m-p/1858561/highlight/true#M81925

Has a factory reset and setup from scratch been performed since last FW update? IF this doesn't resolve anything you can downgrade back to last working FW version. 

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bdela wrote:
I’ve been having a lot of issues with WiFi handoff between router/satellites since this update. Never had any issues before and now most devices don’t hand off when I’m moving around my home—I end up having to disconnect and reconnect to WiFi. Anyone else having this issue?

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