Most TVs and appliances have just barely good enough WiFi to start with. So toss more gear in the area and it could drop.
My usual fixes are to get the WiFi source (router? WAP? other?) inside 20 feet to the TV.
If that doesn't play out I try 802.11g WPA2 on the router then try another router.
If I have my phone on and in the same room as my tv it kicks the tv off the wifi. How do I fix this?

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