Samsung should walk you through check such as firmware and resets. Over WiFi can be troublesome as WiFi is shared and some routers firewall devices. You must be in control of that. I've seen "it worked before" and found the ISP changed settings in the ISP supplied router "for security."
I have a Samsung UE49KS7005 TV and a HW-K660 Soundbar.
Since i bought them 2 months ago i have been using wifi to connect them, not bluetooth.
Now suddenly there is no sound when they are connected via wifi.
But when i connect them via bluetooth the sound works fine.
I can still pair them via wifi as usual, when i use the tv remote to adjust volume, i can see the volume on the sound bar raising/lowering.
Internet connection is ok.
I have tried to reconnect the soundbar to wifi, did not change anyting.
When i use bluetooth the sound is laggy, which is why i have been using wifi.
Please help.

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