[H] Support • Problem of MultiRoom with h6400

During 2 years I have been watching music on YouTube app from smart hub.
To have a great sound I have connected 2 Samsung wam M7 MultiRoom speakers in stéréo mode.
Very easy to connect with MultiRoom app from smartphone or directly in sound menu of h6400. Very nice for 2 years...
But à few weeks ago some problems hapened with sound. (Micro cuts about 1sec each 2mn...)
Very annoying
I tried a lot of things to solve this... even downgrad from last software to 2130..., change wifi card on TV...
But the problem goes on...
Does anybody can help me, please ?

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