Please disable my WiFi 2.4 channel “optimisation”

[prawlin]

I tagged onto a similar thread, but then I suddenly remembered historically that is taboo on these weird TT forums. So before I get chastised by the net police, I’m starting my own thread here.

I have an issue when using my expensive Sennheiser digital cordless headphones. I had the issue a long time and only recently realised what is going on.  The headphone transmitter and receivers unfortunately operate slap in the middle of the shared WiFi 2.4 band (but not using actual WiFi protocol). They use a proprietary FHSS system. I’ve learned that when my router is on Ch6 it makes the headphones frequently but intermittently drop out. If I set my Sagem TT router to channel 13, all is good with all my many (2.4 only) WiFi devices and the headphones operate perfectly. I can prove this with my RF spectrum analyser. I have set many of my connected devices to use only 5GHz WiFi. If I could disable WiFi 2.4 I would do. However, many of my devices won’t support 5GHz, so I have to leave it on.

Very annoyingly the router will switch itself back to Ch6 after a day or two. 
I’ve read on these forums that this is called Auto optimisation, and it can only be turned off by TT support. So PLEASE turn it off on my TT router ASAP!  Thank you and regards. Peter (long term very loyal TT customer)

[prawlin]

Ok so a bit of an update.

Debbie kindly logged a complaint Monday.

On Monday I received several daily ticket acknowledgements then an “Escalated to complaints manager”.

On Thursday I received a phone call (despite my specific request not to use phone). I tried to explain to the person what my issue is. Unfortunately, it soon became very clear he had zero technical comprehension of WiFi channels, or router configuration settings Etc. I got the distinct impression he wasn’t really interested and was also in a rush. Anyway, he said leave it with him and he would consult the technical team then get back to me.

Within 10 minutes of that call ending, I received an email (my name is spelt incorrectly also not that it matters)……

Good afternoon Mr Rowlinson,

Following our phone call earlier I have spoken to a member of our tech department here at TalkTalk and unfortunately we are unable to isolate channels - we can only isolate bands so either 2.4 or 5. I would maybe recommend getting a router that can do what you require and attach it to the current WIFI hub you have. 
I sincerely apologise that we are unable fix this. I hope you manage to resolve this issue.
 

Kind Regards 
(name removed)
Executive Complaint Manager

Then adding insult to injury, within literally another minute I got Text saying case is Resolved and closed so had no option to even respond to the email.

I'm pretty confident that the technical person that was consulted was not given a useable explanation of my request, so came back to the complaints guy, with a standard can’t be done sort of answer. Having technical discussions via a non technical third party is never going to work.

So I give up, a sheer waste of everyone’s time frankly. 

Thanks Debbie for trying, but unfortunately your colleagues did you no favours on this one.

Cheers. Peter.

[Debbie-TalkTalk]

Hi Peter

I have left full notes on the complaint. If I could switch this off for you I would, however our Devices Team have asked us to leave this switched on.

The complaints manager can investigate this further and discuss this with you.

[prawlin]

Thanks Debbie.

I don’t see my request to disable the WiFi optimisation as a “complaint”.  Though I suppose the fact that I cannot switch it off myself (and now neither are you now permitted to apparently) does constitute a kind of complaint. It’s my router, operating in my house, surely I should have control of all the settings permissions as I wish? If I substitute another make of router, I would have full control. Why should TT be any different?

I hope whoever picks up this case can have access to this thread and has a level of technical understanding. I really don’t want to have to explain it all again. All the info details are in this thread.  Anyway, we’ll see what transpires. 
Thanks Again Debbie. Peter. 

[Debbie-TalkTalk]

Hi Peter

I have added all this information to the complaints notes and the complaints manager will contact you to discuss this further.

Thanks

Debbie

[prawlin]

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@Debbie-TalkTalk wrote:

Hi Peter

I completely understand. I can raise a complaint and ask a complaints manager to contact you by email to discuss this further?

---

Yes please Debbie. I find it very irritating that this automatic Channel selection is enforced upon me. I will resolve this one way or another. If TT cannot disable this very annoying feature for me, and allow me to select my preferred WiFi 2.4 Channel,  I will have no choice but to abandon the TT router in favour of some alternative model. That is a real pity as in all other respects this router is serving me very well and I would prefer to stay with it if I can get this issue sorted. Cheers Peter. 

[Divsec]

Hi @prawlin, sorry for this long saga, my solution in the past has been to buy my own router and then I can set it up just how I like it. Then if I have problems just pop the T T router back on so the the fabulous Debbie can help me sort out the line.

Sorry it is a money solution but for worth it in the end. 

D

[Debbie-TalkTalk]

Hi Peter

I completely understand. I can raise a complaint and ask a complaints manager to contact you by email to discuss this further?

[prawlin]

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@Debbie-TalkTalk wrote:

Hi Peter

Thanks for your reply.

Our Products Team have asked us not to switch off WIFI optimisation now.

 I can ask our faults escalation team to take a look at this for you. Would you like me to ask the team to contact you to discuss this further?

---

Aha. Now I understand. Thanks for that. 
Well if it is likely to end up with my specific request being fulfilled then yes please do that.

However, if I’m just going to get an educational lecture as to why it’s not advisable or permitted to switch it off, and then still not doing it then frankly there is no point as it is wasting everyone’s time. That would be a very disappointing outcome, as the router has been wonderfully reliable in all other respects. This compulsory auto Channel switching/optimisation is a real PITA for me. It probably works well for most scenarios but in my situation it is so very annoying. 

I am happy to discuss it via Email, SMS, or this forum but I prefer not to receive phone calls if possible please.

Thanks again Debbie.  Peter

[Debbie-TalkTalk]

Hi Peter

Thanks for your reply.

Our Products Team have asked us not to switch off WIFI optimisation now.

 I can ask our faults escalation team to take a look at this for you. Would you like me to ask the team to contact you to discuss this further?

[prawlin]

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@Debbie-TalkTalk wrote:

Hi @prawlin 

We are unable to switch off WIFI optimisation.

Have you recently rebooted the router?

---

Hi Debbie

I only reboot it occasionally, if when things fail to connect which is rare. Last time was a few weeks ago. Are you suggesting I should reboot it now, and will this then allow you to turn off the optimisation as per my request?

I don't understand why you say the WiFi optimisation cannot be switched off as I request? I see just a few weeks ago, you yourself switched it off for another customer and it fixed his (admittedly quite different) issue here see message #9…….

https://community.talktalk.co.uk/t5/Broadband/WIFI-OPTIMISATION/td-p/3034690

I know my own issue is as a result of my Sennheiser headphones design trying to use the same frequency range as WiFi 2.4GHz uses hence why the headphones malfunction. However, I have also proven by manually changing the WiFi channel the router uses I can fix this issue completely. That is until this nuisance optimisation thing kicks in again and changes my WiFi back to Channel6 (which is the worst possible channel for my situation!)  Please can you switch off my WiFi optimisation as you did for the other customer recently? That is all I’m asking for. Then I will have full control over the WiFi channel that my router uses. 

If you still can’t do this for me, then please explain to me why not as you have clearly done it very recently it for other customers in order to solve their own issues.

Thank You. Peter

[KeithFrench]

From the way that I understand this problem @Debbie-TalkTalk, the headphones seem to be using a part of the 2.4GHz RF spectrum (not WiFi) that the 802.11 WiFi also uses. Therefore this is not Wi-Fi interference, but the two services are conflicting with each other. I think from what the OP has said, things work OK when he has control of the WiFi channels. However, this is a complex situation & I do not know the other RF usage from a technical standpoint to help any further on this.

[Debbie-TalkTalk]

Hi Prawlin and Keith

Are all other devices working ok?

[KeithFrench]

Hi @prawlin 

I really do not see what TalkTalk can do about this, as it does seem to be a problem with these headphones.

[Debbie-TalkTalk]

Hi @prawlin 

We are unable to switch off WIFI optimisation.

Have you recently rebooted the router?

[prawlin]

The headphones do not use WiFi protocol Keith. SSID is a WiFi protocol thing is it not?
I don’t know anything about the proprietary Sennheiser digital protocol. I assume it is not even published anywhere. 

It uses a spread spectrum FHSS (bidirectional) broadcast from the Transmitter to the headsets that just happens to use the same licence free 2.4GHz ISM band. As such, interference between the very many users of the band is to be expected. WiFi is just one of the many users of the same 2.4GHz radio band unfortunately.  As I said earlier, Sennheiser made a poor choice of radio bands to use with 2.4GHz. It’s pretty obvious many user will want to use these headphones in a home situation where WiFi will always be present. Maybe they thought their protocol was sufficiently robust so to tolerate some packet losses when WiFi is present in the near vicinity? They got that bit wrong, clearly.  

It would have been much better if the HP did actually use WiFi linked via the router, then they could coexist with all the other WiFi networked stuff, and this interference would not be an issue. 

https://en.wikipedia.org/wiki/ISM_radio_band

https://en.wikipedia.org/wiki/2.4_GHz_radio_use

No sign of the TT CS yet? Though I expect they will have a backlog after the bank holiday weekend. I see the router pops up on a different Channel 1,6,11 every time I look. I can get an evenings headphone use if I set router to C13. Next day it’s always moved to one of the others, usually C6 which is the worst one for my headphones to co exist with. C1 or C11 is better but C13 is best for me.  Cheers. Peter

[KeithFrench]

Do the headphones broadcast out their own SSID then?

[prawlin]

Ok, just for technical interest ……..

Router on C6 and HP filling band!Router alone on C6 no HPRouter C1 yell. C6 green. C13 purple.3 router chans yell,green, purple. HP on Red

[KeithFrench]

Yes just use the Include Photos button on the toolbar.

[prawlin]

Hi Keith. 
Thanks for the suggestion. It is a good one. However my router is already on 20MHz bandwidth (and has been for years).

It is the headphones that are really the cause of this issue. A poor RF design choice IMHO.  They use a strong  frequency hopping system which literally operates across almost the entire 2.4 band. It centres on CH6 but some packets can be seen within Ch1 and Ch11 pass band on my spectrum analyser. Ch13 is *just* clear of the HP transmissions but with zero guard band between the HP signal envelope and CH13. There is no possibility to change anything on the headphones. My Router is a bit closer to me at my usual listening HP position than the HP Tx is. This obviously won’t help the situation but I can’t really change that easily.

I appreciate your helpful input suggestions, but I’m certain disabling the auto ch selection will resolve it for me. (PS I’m a retired electronics engineer so do have a reasonable understanding of this stuff). I might try to capture some analyser screen shots just for interest if I get some time. It’s astonishing to see how the HP packets totally obliterate the 2.4 WiFi band. It’s amazing that the WiFi appears to work normally even on Ch6 whilst the headphones are switched on. Presumably WiFi has really great error correction algorithms that deal with the inevitable packet burst collisions.  Will this forum allow image attachments ?

I use the headphones literally on a daily basis for late night TV viewing. My walls are thin and my neighbours retire early. I don’t want to disturb them. Also, my hearing isn’t as good as it used to be so headphone listening gives me a big clarity boost. The Sennheiser HDR 185 give me fantastic quality audio performance throughout the house and garden (when they’re not being zapped by my router!). 

Thanks again. Peter

[KeithFrench]

Hi @prawlin 

In light of what you said on the other thread:-

"Yes I know about the old overlapping channels rule. But Though moving from Ch6 to Ch11 helps to reduce my interference to my Sennheiser headphones However it does not eliminate my problem. The Sennheiser uses very wide FHSS occupying much of the 2.4G band, centred around Ch6! but still spilling into C1 and C11. It just clears C13. Hence why it’s my preference in this case. 

I tried Ch11 during my extensive testing and it still reverts to Ch6 anyway.  So either way I still need the compulsory optimisation turning off on my router. I think it’s ridiculous that I can’t turn off this “I know better than you do” auto optimisation feature. Heck I can change a thousand other potentially destructive settings myself so why not this one?"

This sounds to me like the router is set to allow a 40MHz channel bandwidth within the 2.4GHz band, which is another definite no, no. This is very counterproductive, as a 40MHz channel uses up 9 out of the 11 possible channels. This will cause you to have a dramatic loss of performance, not to mention any other nearby networks, as it will cause them massive interference as well.

Please set your channel bandwidth in this band to 20MHz only. It is not your cordless headphones that are mandating this bandwidth, it is totally the router that is in charge here. Alas WiFi Optimisation in my testing does not enforce 20MHz only, so you will need to change this yourself.