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roztom

join:2008-07-24
Oak Park, IL

[General] Random DTMF Tones

I am getting random DTMF tones. Sometimes the listener gets it and I don't hear it, other times I get it and they don't.
I have tried a hardwire phone and a Dect 6.0 cordless. No difference. There seems to be no common factor in this issue. BTW, it happens with male voices...just a mention because I've read that high frequency female voices can cause tones to be generated. (Don't shoot the messenger)

My DSL speed is 438/2.5. Great thruput. Whole House splitter. VOIP Speed test shows jitter around 0.2. QOS 96-99%. MOS 4.2

MY ATA is a Sipura 2102. Upload speed set to 325K. Codec G729.

ATA behind a WRT54G router. All necessary ports forwaded.
QOS enabled in WRT54G, by port priority.

Anybody have a solution for these tones? Is it a ATA bug or is there another solution?

Thanks,

Tom


ArgMeMatey

join:2001-08-09
Milwaukee, WI
kudos:2
Reviews:
·voip.ms
·AT&T Midwest
·Time Warner Cable
It's not uncommon. I have this problem too my SPA-3000. Makes me wonder how often this would happen on a regular switch if they left the receivers on all the time.

You can try upgrading (or downgrading!) the firmware. You may also be able to change the touch tone receiver sensitivity ... I don't remember all the settings offhand.

roztom

join:2008-07-24
Oak Park, IL
reply to roztom
I would expect this is somewhat common.

I assume many have had this issue since I see it mentioned in a lot of forums and on a Google search it comes up a lot.

It might be specific to Linksys Sipura Router/ATA's. Then it might be a generic VOIP issue.

IF anyone has more info on this please drop a line. Are their any adjustments or firmware updates that address this with either the WRT54G or thew Sipura ATA router?

THanks,

Tom

jay_rm

join:2002-04-12
Netville
reply to roztom
..it's a phenomenon called "talk-off".

To put it simply, random tonal qualities in regular speech will trigger the DTMF generator in the TA to produce a 'touch-tone'. It's been said female voices (or voices with more 'highs') do it more then male voices.

In the "old days", Bell Labs spent a LOT of money and man hours to minimize the problem. It's not something you can fix, except by maybe swapping for a different brand of TA.
--
3500/512 5.7 GHz Motorola Canopy Wireless; FoxValley.net
"Peace through superior firepower"

roztom

join:2008-07-24
Oak Park, IL
reply to roztom
Is there any general info on which routers have and those that don't have the problem?

That would surely simplify the issue wouldn't it..

Thanks,

Tom

hwittenb

join:2003-12-20
Reviews:
·Future Nine Corp..
Based on what jay_rm says, I would think if you really wanted to stop sending the tones and you had no need for sending dtmf during an in-progress call you could set the dtmf transmit method to inband. When dtmf is sent as inband there are no special out-of-band packets sent for dtmf digits, the tones are simply part of the voice stream. Of course, with that inband setting you need to be using the uncompressed G711 codec for any chance of actually sending dtmf tones during an in-progress call.

I don't think this would stop the tones coming to you that are being sent by the distant called party.

priller

join:2000-10-20
Gainesville, VA
reply to roztom
said by roztom:

MY ATA is a Sipura 2102.
Take a look at the release notes for 5.2.5. They have specifically addressed the talk-off issue.

»www.linksys.com/servlet/Satellit ··· ondetail

roztom

join:2008-07-24
Oak Park, IL

2 edits
reply to roztom
Good idea on the firmware update. I didn't know this issue was addressed.

I have emailed my VSP about this firmware and if it might be a step to take to deal with this issue and also if it is compatible with their server setup, etc.

When I get a reply I will copy it here.

BTW, I tried the inband thing and while I could make outgoing calls, the VMail would not read my password tones...

Tx,

Tom

hwittenb

join:2003-12-20
Reviews:
·Future Nine Corp..
reply to priller
said by priller:

Take a look at the release notes for 5.2.5. They have specifically addressed the talk-off issue.
It looks like they introduced the DTMF Tx Mode Normal/Strict settings for this purpose. Strict allows you to increase the duration of the dtmf tone before it is picked up as a dtmf digit.

DTMF Tx Mode

DTMF Detection Tx Mode is available for SIP information and AVT . Options are: Strict or Normal. The default is Strict for which the following are true:
•A DTMF digit requires an extra hold time after detection.
•The DTMF level threshold is raised to -20 dBm.
•The minimum and maximum duration thresholds are:
• strict mode for AVT: 70 ms
• normal mode for AVT: 40 ms
• strict mode for SIP info: 90 ms
• normal mode for SIP info: 50 ms


The ATA Admin Guide also mentions another feature which I don't find on my SPA3102:

DTMF Tx Strict Hold Off Time:
This parameter is in effect only when "DTMF Tx Mode" is set to "strict," and when"DTMF Tx Method" is set to out-of-band; i.e. either AVT or SIP-INFO. If a user inadvertently sets the value to less than the default value, the system checks and reverts to the default value. There is no max limit on what the user can set of this parameter. A larger value will reduce the chance of talk-off (beeping) during conversation, at the expense of reduced performance of dtmf detection, which is needed for interactive voice response systems (IVR).
Default is 90ms.

roztom

join:2008-07-24
Oak Park, IL
I upgraded the Sip 2102 to 5.2.5 firmware. I am not exactly sure what the settings are on the DTMF but I "assume" the default is set to address the talk-off issue.

I do have admin access so I will check it out based on what is in the firmware info.

Thanks for the heads up priller & hwittenb and the other contributors.

I will let you know if this firmware upgrade addresses the random dtmf tone issue.

I also set my codec to G711.

Thanks,

Tom

roztom

join:2008-07-24
Oak Park, IL

1 edit
reply to roztom

Re: [General] Random DTMF Tones/SP2102 Frmware Upgrade

I upgraded my SP2102 firmware to 5.2.5

In the Spec sheet they recommend some DTMF settings. The default ATA settings for the upgrade are different from the Spec sheet.

Default Settings on upgrade:

DTMF Protocol Info: Yes
DTMF PRocess AVT: Yes
--DTMF TX Method: Auto
--DTMF Strict Hold-off TIme: 40
DTMF Tx Mode: Strict

Spec Sheet:

NOTE: The different recommended settings for AVT transmission are as follows:
–– DTMF Tx Method: AVT

–– DTMF TX Strict Hold-off Time: 70

Can anyone tell me if these differeces are material?

For the timebeing I am going to run in the default setup and see if it addresses the random tone problem.

Will update after I see how it works.

Was on phone for an hour..Listener heard one tone..I didn't hear anything. I changed the settings as Specified and referenced above from the default.

I will advise if this has any impact.

BTW: My VSP did not know about the firmware update....

Tx for all your help.

Tom

roztom

join:2008-07-24
Oak Park, IL
reply to roztom

Re: [General] Random DTMF Tones

Have any of you done this Firmware upgrade?

If so what is your experience with it?

I am still getting DTMF tones from time to time... maybe even more...

Tom


DogFace05

join:2005-12-09
Cary, NC
kudos:154
Are you getting the tones, or is the remote party getting them?

Tones that you hear, are caused by the other party's adapter misdetecting DTMF tones, in conjuction with it being configured to deliver the tones out of band. These tones are then regenerated by either the VoIP provider or your adapter. There's nothing you can do to your adapter to fix that. It has to be done at the other end, ie the remote party's ATA.

On the other hand, if it's the remote party that hears the random DTMF tones, it is your ATA that is responsibe for causing them. Only in this case can you adjust settings on your adapter to eliminate or improve the issue, but only for the other end's benefit.

roztom

join:2008-07-24
Oak Park, IL
The other side are using POTS or Cell. I do not hear the tones most of the time but sometimes I hear and they don't.

Tom

roztom

join:2008-07-24
Oak Park, IL
reply to roztom

Re: [General] Random DTMF Tones/ UPload UPDATE

(Copied from Another Post/UPDATED DATA/UPload Discards)

Improving Upload MOS VOIP Quality

Greetings:

Here are several intermittent issues I have with my VOIP Intermittent random DTMF tones (have latest SPA2102 Firmware update 5.2.5 to address this) and Intermittent Disconnects.

I have been trying to track them down. Let's assume for a moment "everthing" has been tracked down and is up to snuff with the possible exception of the following:

I have been testing my upload and Download MOS. My upload Mos Score is almost always lower than my download.

Using the G711 Codec I am typically running 4.1 - 4.4 on the upload side. Download side is usually 4.3-4.4, as good as it gets for that Codec.

Here are several questions for you who are technically astute:

AT&T ADSL: 485/3.0 (get apx 408/2.5)

On the upstream I often see the following (inconsistent, of course):

Packet Discards: 1.0 - 2.0%
Packet Bursts (Occasional)
Jitter appx 100 - 150ms.

I am curious as to how sensitive my VOIP would be to this and if it is the cause for some of the intermittent issues I am having OR are these numbers within tolerance for a good MOS? Should those upside MOS numbers be good enough for a consistent quality QOS?

Also, where would I look to troubleshoot the burst loss, packet discards and jitter? I do not have any significant amount of these on my downstream, which leads me to believe that my line side is ok. Have switched out modems. Modem in Bridge mode. Router WRT54G. THis is not consistent, sometimes upload MOS is 4.4 also. I understand that with ADSL up & down can run 2 different routes but the upload is consistently under-performing the download. SInce UPload seems to be where the discards, bursts are, is this an Router or an ISP? Can I do anything on my end to address this? Can a better QOS control have an impact. Currently mt ATA sits behind my router, should I put it right after the modem in front of the router?

Thoughts, suggestions?

Thanks,

Tom

priller

join:2000-10-20
Gainesville, VA
said by roztom:

Jitter appx 100 - 150ms.
Are you getting that number from the SPA call statistics?

I have never seen anything higher than 2-3ms ... 100+ is plain crazy.

The DSL can be provisioned differently. As is recall, there is Fastpast and Interleaving. Can anybody comment on if that would make a difference?

venk25

join:2004-05-12
Nashua, NH
I thought the DTMF tones were provider specific. I have VoicePulse and I hear tones - well, now that I think about it, I haven't heard recently. I use two other providers extensively and don't recall hearing tones with them at all.

roztom

join:2008-07-24
Oak Park, IL
reply to roztom

Re: [General] Random DTMF Tones

MY DSL is set to Fastpath.

The issue that seems to be the most constant issue effecting my Upload MOS are the packet discards..

Any idea why this only seems to be happening most of the time on the upleg?

I have actually around 410kb up. Should I adjust my QOS to 80% of available upload so it doesn't get saturated?

I am curious as to why this is only happening on the upside..any ideas?

I have the WRT54G router. Does this router have a history of poor upload management or anything else or is this probably all ISP related?

Thanks for your time and interest.

Tom

roztom

join:2008-07-24
Oak Park, IL
reply to roztom

Re: [General] Random DTMF Tones/UPDATE

I updated my SPA2102 to firmware 5.2.5 that addresses the Tone Issue. I adjusted my DTMF tones as per the spec on the Linksys site (not the default settings.

My random DTMF tones have dropped substantially.

I occasionally still get a few but sometimes not for a day or 2, then there is one. I haven't found any consistent situation that causes it from my end.

Thanks everyone for your suggestions.

Tom