Do not factory reset any Sonos speaker. Try removing power from the soundbar and TV. Wait 30 seconds. Restore power to the TV and then the Arc Ultra to let it come back and reconnect with surrounds and sub. Make sure the HDMI cable is secure on both ends. Turn on your TV.

If the issue persists run a diagnostic and record the reference ID number. Do not post the reference number in the community due to privacy concerns. Call Sonos tech support to discuss the data.

Let us know the outcome on either of the above suggestions. 

Thanks a lot my friend ! I have already done what you said . It didn’t work! The support center will make a replacement because of a warranty ! 
 

Refresh : Now that I use my Sonos system via YouTube it works perfectly… 

Is there any possibility my TV will be responsible for all these weird sounds… May be the eArc port be burned ?? 

Did the diagnostic reveal anything or did customer support replace the Arc Ultra carte blanche?

Well if you reproduce the conditions that prompted your post with your replacement and the same noise occurs then it’s a safe bet that your TV is at fault. Then again if not it could have been the fault of neither one…just a strange occurrence.