It happened to me as a very loud white noise (10 secs or more) while I was watching Apple+. The dog jumped and I got scratched all over and the only solution was to take it off the power. I am letting it go, won’t be powering it again.

I’d guess it’s a decoding glitch and you are hearing the raw data instead of the decoded audio.

I still have some dts surround audio files hidden inside flac files from back in my squeezebox/early zp80 days, which will produce white/screaching/data noise when trying to play them back now.

Back then, my avr could decode dts, but the audio streamers couldn’t because they only supported stereo. Setting them to bitstream to the digital output with fixed volume, meant they would decode the flac container file and pass the dts audio contained inside through to the avr to decode because they didn’t do any processing on the decoded data before outputting it.

That no longer works and attempting to play the files now just produces raw data noise because it isn’t actually stereo audio inside the flac container, but a 6 channel dts stream and players want to perform additional processing before sending to the digital output.

Example Flac file

Audio
Format                                   : FLAC
Format/Info                              : Free Lossless Audio Codec
Duration                                 : 48 min 40 s
Bit rate mode                            : Variable
Bit rate                                 : 1 262 kb/s
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 44.1 kHz
Bit depth                                : 16 bits
Compression mode                         : Lossless

Actual audio content of the same file decoded using flac defaults and saved as a wav file

Audio
Format                                   : DTS
Format/Info                              : Digital Theater Systems
Codec ID                                 : 1
Duration                                 : 48 min 40 s
Bit rate mode                            : Constant
Bit rate                                 : 1 411.2 kb/s
Channel(s)                               : 6 channels
Channel layout                           : C L R Ls Rs LFE
Sampling rate                            : 44.1 kHz
 

The above is what used to be bitstreamed to the AVR without any processing by the player.

I recently (July 2024) started having similar random high pitch squealing noise from my Arc. When I looked at the Arc I noticed the mic was turned off. I turned it on and the noise instantly stops. If I turn the mic off the noise doesn’t return. 

Hi all ! I have Arc , 2 fives and sub3 and i have the same scary issue. If you check reddit @   

  Sonos ARC sounds extremely “tinny” “metallic” and “thin” sounding : r/sonos (reddit.com) you will find A LOT of users, hundreds of mad musiclovers…. that is having the same problem. Reading the posts gives me an understanding that this IS A REAL hardwareproblem, but Sonos tries to aim at new updates for firmware or talking to support “on your specific problem” or “roomsize” etc.

THIS is so sad for me and for you all.

I bought my system above because of my neighbor that is having the older sonos “soundbar” and the smaller sonos older speakers and the older sub and it sounds fantastic both the treble, midrange and the bass AND it follows up in volume with the same sound NO oversteering of any frequensy and we have played LOUD…fantastic sound.

So i bought the latest sonossystem above and are so dissapointed, i thought it would be even better compared to my neighbours older playbar of course.. but NO.

If you play Phil Collins, any song you will easily find the issue on the Treble, Midrange hollow/metallic sound in his voice and it sound like hurting the ear..as my son said who are a swedish musicproducer.  This problems are not only Phils voice it is a lot of others of course but Phil does have a Treble/midrange voice that is showing the problem really easy. Even Lady Gaga are in the same level of frequens of her voice. 

Hope that Sonos will take care of this and become “returnfriendly” to us all or have some other idea of solving this and i am all ears so to speak..

Sorry for being so negative but i feel scammed this far and now it is up to Sonos / Hifi Klubben to solve it.

Best regards

Hi all I just purchased my Sonos system a month ago and  while the TV is off The arc will admit a very loud thundering humming type noise. It’s loud and it’s deep and last about three or four seconds. Definitely can scare somebody as to why the system is still making sounds even though the TV is off. I hope they come up with a solution as if it happens in the middle of the night it’s not going to be good.

I’ve never heard it when the system isn’t playing. 

Yep it made the sound about three times. All randomly. All with the tv off. I just sssumed that turning the tv off would turn off the Sonos  devices but I guess not. 

The only true way to turn off a TV these days is to unplug it. When it appears to be ‘off’, much of the TV other than the screen is still active, looking for data coming in, and passing that data on to the Sonos. 

There have been reports in the past of software updates being made to cable boxes which send ‘noise’ to the TV, which then passes it to the Sonos via ARC. 

The best way to be sure about where this noise is really coming from is to submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

Ok will do the next time I hear it. Thanks!