Hi all, another update from me:

I have now gone through 4 units of Sub gen 3 and have finally found one that is “good enough".

It does still have the hiss/crackling sound, but from this unit I can only hear it from 5-10 cm away.

The other 3 units I have tried I could hear it from 3 m away.

Still hoping for a permanent fix from Sonos, but I fear that it might be hardware related?

Received my Sub gen 3 a couple of days ago and found that it made a mains hum/crackle sound too. I spent over an hour talking to technical support and sending them videos of the problem. Eventually they agreed to send a replacement which should arrive on 23rd November. However, after reading this thread I don’t expect the replacement will be any better. I guess this is a hardware issue and won’t be resolved until they design out the flaw.

This problem seems to go back over 4 months. Why did they act like they had never heared of this issue before? This lack of quality and support is definitely not what I expected from Sonos. Do they even bother to read posts on their own forum?

I have the same issue. Last week ordered the sub gen 3 and arc. When the sub is Connecting with the arc the static noise starts. Hopefully Sonos Gets it solved.

I have this EXACT issue! What is the recommended course of action? I am in Canada. Thank you.

Should I contact support and reference Andrew's case number?

@TwoBiteBrownies 

Yes, I’ve shared the case number with you and just reach out to the customer service. It seems to me that this is still happening with the new units, I hope they can resolve the problem for good and send a perfectly working replacement as I think the issue seems quite wide spread.

@andrewchiu1st 

Your case file must be very long lol. The support worker has been reading it for a good 15 minutes

Update on my end: Spoke to support worker. Didn't even need to send in a video or do diagnostics. I just put my phone up to the Sub and he could hear the insanely loud ticking/hard drive-like noise. He insisted on a replacement, but I told him I didn't think that would work based on what I read on this thread. After referencing @andrewchiu1st 's case number he told me that a replacement solved the problem for him. I asked again because I wasn't so sure, but he insisted. 

This Sonos agent I pray to God is right because I am physically walking this sub 20 minutes away to return it. I don't own a car and told the agent that I would legit need to carry the sub to return it because I cannot use Uber / Don't have anyone in my bubble that drives (Covid). He once again insisted that a replacement would solve my problems and that they would check that it works before shipping out my replacement. Can @Krishma M confirm that this agent is correct before I break my back returning this sub? Thank you.

Edit: Just learned that they do scheduled pickup. Wish the agent would have mentioned this because he just kept saying "don't worry". Breaking my back is no longer a concern of mine. Hopefully the replacement will fix this.

Hmm, I wish the replacement did solve my problem, haha! I requested 1 replacement, but it still has the same problem.

When I last checked with them, they wanted to offer another replacement but when I saw that people who purchased the device only recently are still having the same problem, I have some doubts that another replacement is going to solve the problem if it’s an issue with the production.

@Krishma M Considering that this is  a production issue, will my return window be extended for keeping a defective sub? From my understanding you only have something like 45 or 60 days to return the product. Once this issue is fixed in your production can I contact you guys and get a guarenteed working replacement even if I am not within the prescribed timeframe to return?

I got my Sub yesterday, in Canada, the same noice as described by many here. 

serial number: 54-2A-1B

hardware version: 1.32.1.4-1.2

Just might have to return it, or I can hold on if Sonos guarantees a replacement when problem is fixed. I will wait for two days for any Sonos reply with a conformation on the, if not it’s going back to the store in two day.

Cheers.

I did go through 4 Sub = 3 replacements

Sub #1 and #2 sounded equally bad

Sub # 3 was even worse 

= all 3 of these I could hear a high pitch hissing and crackling noise from more than 3 meters away!

Sub #4 was ALOT better, but not perfect.

I can still hear the noise, but only from about 10-20 cm away.

Still, I am awaiting a permanent solution and hope that I will get a fully working replacement once  the fix is in place

Yesterday my sub has been replaced. The static  sound is still there but not as loud and anoying as my first sub. So happy for now, hopefully sonos can fix the last bits via software.

I’m in the same boat, Belgium

SN: A200 2009CP 54-2A-1B-21-5C-6C-5

I can hear this noise even when no music is playing (by putting my year to the sub), when watching TV (with the Beam via HDMI arc)  the sound is more intensive, I can hear it well from 1m. 

Replacements won’t help as far as I understand here.

Unbelievable, no official response, nothing. What should we do all? I believe the number of actual faulty units is huge.

@Krishma M can you please answer my previous question? I got my replacement and same issue.

Received mine today (Netherlands) and can confirm the issue is indeed still very much there. I'm still testing but would call it deafening in some cases.

Serial 54-2A-1B

Received my Sonos Sub 3 Gen yesterday. I can confirm the cracking noise as well. Very disappointing.

In case that only music is played you can hear a constant sum noise like a harddrive. If sound is coming from TV over the Sonos ARC you can hear a cracking noise in regular intervals that is louder.

i will get in base touch with the Support on Monday.

At the moment I am not sure how to proceed. It seems that replacements do have the same error. 

I bought mine from bol.com (NL), not sure what to do if all units are the same.

Hmmm - Gutted to say that my new Sub Gen 3 is doing the same. This is the my first Sonos system having finally taken the plunge last week. Thanks for the ongoing support of this thread. Will contact Sonos support on Monday. Despite the Sub issue I’m absolutely blown away by the Arc. Ready Player One with the Dolby Atmos sound track was ridiculous! I just cranked up the volume and the humming Sub issue went away (as in drowned out )

Did some more tests. Connected all speakers (ARC, Sub, 2x One SL) using Ethernet to a switch. Disabled WiFI on each speaker.

The cracking noise is gone! In a LAN-Setup the system works as expected.

I am using a FrithBox 7590 as Router in the basement. In the ground floor and upper floor there is a FRITZ!WLAN Repeater 1750E each. The FritzBox 7590 and both FRITZ!WLAN Repeater 1750E build a Fritz Mesh. WiFi is repeated WiFi-to-WiFi on the FRITZ!WLAN Repeaters. At the moment I assume that the annoying noise at the Sonos Sub is caused by this WiFi-Mesh configuration.

Has anyone had this experience too?

What can I change on the Fritz Mesh so that it works with the Sonos system without background noise?

When the going gets tough I replace the Fritz Mesh.But what would you recommend? The WiFi must work on three floors. Preferably with just one WiFi SSID.

Similar experience here, BE market. I think I may be one of the "lucky" ones with a fairly okay sample. Being in the 0.0001% top auditive range of population (since I have become 98% blind) I noticed it right away. As I removed and readded it from the system it went from the rattling to the static noise, which is far less annoying in my opinion. Adding ethernet kind of helped too, but not sure about that. Either way, I can hear it from about 6 metres away but my girlfriend only did when she was holding her ear in the sub (even with 2% vision, a very pleasant sight ha!), which seems less than what some of you are experiencing. Fearful of it deteriorating though. 

I'm planning to contact support and redirect them to this thread, waving the request or counter-proposal for a substitute which is just wasting their time really, especially in this pandemic situation. I hope that legally expressing my desire to return, but only once they are able to replace with a fixed production line extends the window to do so. From the positive help a lot of people seem to have gotten I'd say Sonos cares enough not to screw its' customers over on such technicalities. That alone is rare nowadays. 

Wishing the best to all fellow sub-owners and the people at Sonos who are probably stressed out of their mind to adress this as the complaints roll in. We don't buy these on the short-term, a solution might not be found in such time either. Hopefully they can find a way to fix and replace case by case rather than recalling. 

Received my replacement unit today (NL). Same serial range 54-2A-1B but is definitely does not have the issues. 

When no music is playing and I place my ear almost inside the hole I can here a very silent small zoom, but I definitely can't hear it when I'm in the chair next to it and it doesn't produce all kinds of side noises when music is playing.

Happy! And probably lucky.

If you hear that idle static noise when putting ear to the sub, you should be also hearing it when music is playing (by putting year to the sub).

Latest conversation with Sonos and they say that they are “tracking the issue”, which is odd because they have so far being denying that anyone else has reported a problem!
 

i have turned down the offer of yet another replacement and will give it a another few weeks to see if they come forward with a properly engineered solution...

I have this issue with a 7 day old Gen 3 sub purchased from John Lewis in the UK.

I created a separate thread as I hadn’t spotted this one, but having read through this in full it is the same issue.

Hardware Version: 1.32.1.4-2.2

Sub has an electrical hum when plugged in. There is a bit of crackle but not as bad as the videos linked in this thread. The hum is louder when the sub is “awake”. The hum can be heard from about 0.5m away. All my other Sonos products are “clean” in that they don’t hum.

I can probably live with it… but I am concerned that it will get worse over time. Given the direction of this thread, I am very tempted to return it as I am inside my “no questions asked” return period with the retailer.

My impression is that this is an issue with the PSU or some other electrical component(s) in the unit. It doesn’t sound like the hum is coming from the speakers themselves, but from inside the sub.