OFDM ANI level 9 everywhere in the house

  • 28 September 2021
  • 13 replies

I started having problems with audio randomly stopping during the day a couple months ago.  I only recently learned about the Network Matrix so I have no idea what it looked like before this started.

I currently have two Play 1’s in each upstairs offce, a Play 5 gen 2 in the living room and an Move in the Kitchen.  When I look at my Network Matrix, both Play 1's and the Play 5 are all showing OFDM ANI level 9.  I have a few home automation devices that are stuck using 2.4ghz, so I figured it might be interference from those.

I’ve pretty much turned off every device in my house, moved the speakers everywhere I can think of and nothing seems to have made any difference.  I replaced my mesh wifi system with an Asus AX6600 and bought a boost to try.  Same thing.  All of the speakers are red, as well as the boost.

I do live in an are with some wifi congestion, but I find it hard to believe that there would be that much interference from my neighbors that it causes the OFDM ANI Level 9 no matter where in my house I place speaker.

I’ve tried making the suggested changes to the 2.4ghz channel on my router.  No difference there as well.  I have tried using a wifi analyzer app, but networking and wireless are not my expertise.

Short of flipping breakers in the house, I’m kind of at a loss as what to try next.  Any suggestions?

Thank you!


13 replies

Userlevel 7

Have you tried disabling Airtime Fairness for both 2.4 and 5GHz bands on your router?


Yes, sorry - I should have mentioned that.  AirTime Fairness is completely disabled and Qos is turned off.

I should also mention, that I’m able to plug one of the Play 1’s in the office into an Ethernet cable.  From the network matrix, the connections using that Play 1 seem to be green, but the drop outs still occur and all of the speakers show red.

Up until a few months ago, everything seemed to work fine.  Sometimes the music will play for hours uninterrupted, and other times I’m lucky if it last five minutes.

Thanks again.  I appreciate it!

Userlevel 7

Have you tried changing the SonosNet Channel in the Sonos app under the Network settings?

Is there any difference if you keep the Play:1 wired but disconnect the Boost completely? Or keep the Play:1 wireless and just use the Boost?

You mentioned “during the day”, does the situation improve at other hours? How are your noise floors? Does your WiFi analyzer show channel width? You may have a neighbor who is using wide channels.

EoP (Ethernet over Powerline) is my absolute last choice for networking, but sometimes it is the magic bullet. While it is immune to WiFi trash, power line trash can be a problem. If you try EoP, don’t plug the units into high end surge suppressors and try to avoid sharing an outlet with a surge suppressor. Large appliances on the same circuit can be an issue. Your electrical panel is arranged in columns. Outlets in the same column work best. If you have multiple panels, EoP does not travel well between panels. The newest EoP units are superior to older units. It’s counterproductive to get a “deal” on an older unit.

I had changed my 2.4ghz channel on the router to 20mhz and set it to channel 1.  I set the SonosNet channel to 11 in the app.

It doesn’t seem to make any difference whether the boost is plugged in or the Play 1.  I only have until Friday to return the boost, so I wanted to make sure it wasn’t going to help me out.  I did plug the boost into ethernet in a different part of the house, and nothing seemed to even use it judging by the network matrix.

I did realize something a little bit ago.  Even if I just play music on only the Move (connected to 5ghz), it too stops after a few minutes.  Not even grouped with any other speakers.  Not sure what that might be an indication of.

Thanks again.

What is the source of your music?

Are the PING times to your network clients reasonable?

The ping times seems to be pretty good to all devices.  Usually around 1-3ms.  The music source is typically SiriusXM.

Good question about day versus evening.  I don’t tend to listen as much in the evening so I can’t really compare.  I’ll have to do some testing.

Currently I’m just using the free Wifi Analyzer app from the Windows store.  I was doing some research on some others, but haven’t figured out exactly how to read the data very well yet.  I’ll look into that some more this evening.

I should mention that I have AT&T Uverse cable and currently both the gateway and the ASUS systems are doing NAT, so I’m in a double NAT situation if that makes any difference.  None of that has changed anytime recently.

I appreciate your help on this!

Double NAT will inflame the hard core network types, but it’s not the end of the world -- unless you are attempting remote access, VPN, etc., then it gets a bit messy. But, you’d already be having issues. If possible, disable the Uverse’s WiFi because this is just clutter.

I use Android devices to host my WiFi analyzers. Apple phone/pads are not as useful because Apple does not make much data available to the API. I have no experience with Windows analyzers.

Your PING times are fine. Tons of dropped packets are not.

I’m sure that you are already aware of this, but just to make sure -- the Network Matrix is a static view, refresh the page for an update.

ZigBee devices can cause WiFi interference.

In an attempt to avoid being blindsided, have you recently tried other music sources?

Thanks Buzz.  The wifi is disabled on the ATT gateway since it’s not being used.  I think all of my smart home devices are Zwave, but I’ll double check and make sure some ZigBee stuff didn’t make it’s way in there.

A different music source is a good idea.  Let me give that a shot tomorrow to see what happens.

Am I correct for assuming that since the Move stops playing the music when it’s not grouped with other speakers, than maybe the 2.4ghz interference isn’t my issue?  The Move is definitely connecting to the 5ghz band and has a great connection to the mesh node.

Thank you!

Don’t assume that the interference is limited to one band.

Are you using the SONOS App to play music? If you are having dropouts to the not Grouped wired unit, I’d be suspicious about something fundamental in the network. Is the wired unit wired to the router or a wireless mesh node?

People have been reporting issues with other ASUS routers. Various “Solutions” have been reported. Full disclosure: I don’t have any direct experience with any recent ASUS routers. Some users report that turning OFF Airtime Fairness is the magic, others report that rolling back the software is the answer, and recently some have claimed that the latest ASUS firmware is magic -- but only if the router is factory reset after the update.

Of course, router updates are not likely to cure ANI level 9 issues,

I did quite a bit of searching before posting so I read about the ASUS related issues.  I’ve tried all of those changes and none of those made much of a difference.

I should mention as well, that the speakers were all in a WIFI configuration (No SonosNet) for quite a while without issue until the drop outs began a couple months ago.  At that point I was on a first Gen Google Wifi setup that had been giving me other wireless issues as well.  That’s when I decided to upgrade to the ASUS setup.  I was getting the same ANI level 9 on the speakers when I was using the Google Wifi.

The hardwired Play 1 is plugged directly into the secondary node, but it’s connected to the main node via ethernet backhaul.

I really appreciate the help.  I’ll keep digging.  I’m still just hoping that interference source is something within my house since it happens anywhere I place the speakers.  If it’s something from my neighbors, I’m not likely to get them to change anything.  Maybe I can get them to move?  :)

You may be familiar with the ancient BSR X-10 system. It is not at all secure and there can be accidental interference between neighbors. A magazine article reported the scheme used by a fellow who had a very elaborate system using dozens of dimmers to create sunrise and sunset lighting. A neighbor was duplicating some of the codes and disrupting the show. Our enterprising fellow set his computer to loop through the whole control space giving miscellaneous commands. Eventually the neighbor gave up attempting to use this “unreliable” system.

While walking your space using a phone/pad based WiFi scanner you may be able to get a sense of the interference origin.

I appreciate your issue because I can have mostly red cells in the left column of my matrix. There is a medical facility next door and various “high tech” nearby homes with unfortunate WiFi channel assignments. I’m still testing. Currently, my SONOS is WiFi.

I wanted to update you, buzz.  I’ve been playing Apple Music the last two days and it’s been solid for 8+ hours each day.  No drop outs at all.

I’ll probably continue to see if I can pinpoint the source of the interference.  More for my own curiosity than anything else.

I’m a little disappointed that SiriusXM seems to be the issue as there are a few stations that I enjoy listening to.  I did some brief research and there are others that have a similar problem.  I’ll probably dig into that and see if I can come up with anything.

Thanks again for all the suggestions!