Is there a settings option on the TV to switch off the standby light? Check you have the latest TV firmware update. Then if problem remains, I would contact Samsung Support. It sounds like a fault with the TV itself. Not seen the issue reported here before, however looking at Google, it is a known fault with some Samsung models. Here are three (of many) non-Sonos-related links that talk about the problem:



https://itstillworks.com/12611522/when-a-samsung-tvs-lamp-timer-and-standbytemp-is-blinking-what-does-that-mean



https://itstillworks.com/12590733/how-to-troubleshoot-a-samsung-tv-that-has-a-blinking-standby-light



https://www.cnet.com/forums/discussions/samsung-led-with-flashing-standby-light-on-front-616859/

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