Sound Cuts Out for Half a Second Randomly

[brentw]

Update - December 17th 2010.
The sound cutouts appear to have been fixed.
Can confirm for sure after a few days to make sure things don't come back.



Update:
Quick summary of updates from throughout the thread.
The issue is every so often, a few times per second to a few times per 10 minute interval, both incoming and outgoing sound cuts out for about half a second.
--the half second cutout is different than choppy voice or echoing which can happen with connection problems, not having QoS setup properly, or other issues etc., this problem is very brief never more than half a second complete sound cutout/silence--

See the attached zip file for 5 audio files that show the problem.
Clips 1, 2 and 3 are cropped around the problem.
Clip 4 and 5 show that it is mostly fine but at the end of each there’s a blip.
All 5 clips were from one call that was about 3 minutes total.

FPL.zip

5 audio sample files

(3.69 MiB) Downloaded 762 times

I have tested using 2 different PAP2T’s.
One was reset to factory defaults and only did the 4 entries to be able to connect to my account to rule out any settings that I did being a problem.
Also purchased a new Grandstream 502 and the same issue.

Tried G711u and G729a codecs, same problem on both.

I always mute the phone I am testing with to make sure it’s not causing the sound to cut out when I make noise on my end...

I also used two different phones on each.
One a year old panasonic cordless that I have been using the whole time back when FPL was perfect.
And a hard wired default Bell phone.
Both behaved exactly the same

I tested using 4 different connections.
Rogers in Markham.
Cogeco in Niagara Falls.
Bell DSL in Toronto.
10meg Fibre in Toronto.
All experienced the same issue.

So that rules out:
ATA device
Phone handset
Internet Provider

The only variables I see left are something on FPL’s end.

Or something to do with all connections around the GTA, including down to Niagara, but the Rogers and Fibre take a completely different path so I don’t see how that would be it.
And also if that was the case it should affect all voip providers, not just FPL.

Maybe the path into FPL, is it different somehow for some accounts/providers vs others?

I really don’t know what other steps I could take in order to find the problem.
To me the only common element is the FPL server.


---Original Post Below---
New problem that has started recently.
When on a call the sound will "blank out" / cutout for half a second, just enough that you have to ask the person to repeat what they just said or for them to ask me what I just said. It is very short, just long enough to miss what word was just said. And it goes both ways, both sides can't hear the other for that half a second or so. I tried timing it the other day and it was all over the place, from 5 seconds to 3 or 4 minutes between it happening.

I have a syslog server setup and here are the entries from around the time that one of the cutouts happened.
Note this call was *98 into the voicemail, so no outside line and it still happens.

I have the same happen with my parents FPL phone too at their house.

See the attached (bottom entry is the first entry, top entry is the last entry).

The main lines I can see that stand out are:
(I changed some digits to # for my IP and phone number)
---
NOTIFY sip:voip.freephoneline.ca SIP/2.0<\0x0D><\0x0A>Via: SIP/2.0/UDP 192.168.75.2:5060;branch=z9hG4bK-8427de70;rport<\0x0D><\0x0A>From: brentw <sip:1289577####@voip.freephoneline.ca>;tag=e2144d6ca19966c8o0<\0x0D><\0x0A>To: <sip:voip.freephoneline.ca><\0x0D><\0x0A>Call-ID: e87b0afc-9e1f4678@192.168.75.2<\0x0D><\0x0A>CSeq: 5666 NOTIFY<\0x0D><\0x0A>Max-Forwards: 70<\0x0D><\0x0A>Event: keep-alive<\0x0D><\0x0A>User-Agent: Linksys/PAP2T-5.1.6(LS)<\0x0D><\0x0A>Content-Length: 0
---
SIP/2.0 480 Temporarily Unavailable<\0x0D><\0x0A>Via: SIP/2.0/UDP 192.168.75.2:5060;branch=z9hG4bK-8427de70;rport=5060;received=173.34.89.###<\0x0D><\0x0A>To: <sip:voip.freephoneline.ca>;tag=f6a7d15c<\0x0D><\0x0A>From: "brentw"<sip:1289577####@voip.freephoneline.ca>;tag=e2144d6ca19966c8o0<\0x0D><\0x0A>Call-ID: e87b0afc-9e1f4678@192.168.75.2<\0x0D><\0x0A>CSeq: 5666 NOTIFY<\0x0D><\0x0A>Content-Length: 0
---
unref domain, voip.freephoneline.ca
---
last unref for domain voip.freephoneline.ca
---

These were the 4 entries that I found that happened around the time the sound cutout for half a second when calling into voicemail.

ISP is Rogers.
ATA is PAP2T with 5.1.6(LS)
Router is a Linksys WRT160N with DD-WRT on it from April 2010.
QoS is setup on the router (and I only have one computer on the connection that was idle at the time).

Update:
and I just tried plugging my PAP2 directly into my modem and the problem persists, so that rules out the router and any QoS.

Any suggestions?
Has anyone else experienced this in the past few days?

Brent

[leeloosh]

I have had the same issue since I joined last summer and can't seem to remedy it.
I set my parents up and experience the same issue. Same router at both houses as
brentw and we are both using Rogers and have SPA2102. My folks are ready to throw
in the towel and it isn't rating high on the WAF (Wife Acceptance Factor).

Any ideas would be greatly appreciated!

[laurent]

I've had that, but I fixed it with QoS. Since the issue happens if you bypass the router altogether, it eliminates that.

Have you noticed if it happens on incoming calls too? The reason I ask is because a different codec is used when receiving a call than when making one. You could disable G729 and only use G711 / PCM / uLaw / aLaw, for kicks. I switched to that codec for better sound clarity, even though it uses more bandwidth.

[brentw]

I bypassed the router, ATA plugged directly into the modem.
Still happens.
It's not a QoS issue or router issue since a router isn't being used.

If you go into voicemail and push 3 for personal options.
Then push 2 for administrative options and listen to the options (longest list in the options I could find where she's talking for a while).
Then push * and listen.
Then do 2 again.
Then *.
Then 2.
*
2
etc

and listen to the menus, then every once and a while it will cut out briefly.

I use G711u for both incoming and outgoing.
Decode latencey is normally about 40ms, jitter is normally about 2ms.

I never noticed this being an issue up until a week ago or so.
I was talking on the phone today and at least 3 different people said oh is that your call waiting?...
That never used to happen.

If you do the voicemail menu test above listening carefully do you get any very brief cut-outs of the voice listing the menus?

[mitwtim]

This is an issue for me too. Sound cuts out for a second, or maybe a fraction of a second. It is similar to the interuption you would experience when you receive a call waiting beep, or the other person does.

[FONGO_steve]

Let me send off a few emails about this and see what I can find out!

[brentw]

I attached some samples of what is happening.
Clips 1, 2 and 3 are cropped around the problem.
Clip 4 and 5 show that it is mostly fine but at the end of each there’s a blip.
All 5 clips were from one call that was about 3 minutes total.

PAP2 ATA was plugged directly into my rogers modem.
This has never been an issue in the past.
My pingtest.net results to the Toronto server are the same as they always have been, ping around 22ms, jitter around 4ms, no packet loss.

[FONGO_steve]

I attached some samples of what is happening.
Clips 1, 2 and 3 are cropped around the problem.
Clip 4 and 5 show that it is mostly fine but at the end of each there’s a blip.
All 5 clips were from one call that was about 3 minutes total.

PAP2 ATA was plugged directly into my rogers modem.
This has never been an issue in the past.
My pingtest.net results to the Toronto server are the same as they always have been, ping around 22ms, jitter around 4ms, no packet loss.

Would you mind PM'ing me the details of a call where this happens? Ie. date/time/phone numbers involved? I've been playing around here this afternoon and haven't been able to duplicate it, but I have witnessed this once before, so I just need to track down what variables/devices it's affecting.

[brentw]

PM sent.

Thanks Steve!

[techevo]

I'm experiencing the same thing today. Sound quality is usually good but I used the phone quite a bit today and it was pretty bad.

[laurent]

Just to chime in that I've had over 35 minutes of calls today and the sound was perfect, not a single glitch. This issue seems to only affect a few accounts, not all of them.

Interesting points:
- I use G711 both ways.
- HT502 behind a LInksys WRT54GL running Tomato/MLPPP with QoS set properly.
- Today's calls were all outgoing.

Other interesting point: Everyone in this thread with the issue has a Linksys PAP2 ATA. An incompatiblity perhaps?

[FONGO_steve]

Other interesting point: Everyone in this thread with the issue has a Linksys PAP2 ATA. An incompatiblity perhaps?

That's one thing I've also noticed - I haven't been able to duplicate this using my Grandstream HT-286 here in the office. I'm going to try and dig up a PAP2T to play around with later on - I'm wondering if there's a setting somewhere relating to call-waiting that needs to be modified.

[brentw]

So it looks like there is some congestion/packet loss in a network called cogentco.com.
See attached jpg.

Could someone else try downloading this program and doing a test and see what you get?
It would be really interesting to see if it’s all Rogers customers being routed through this network.

This seems to be a lot of the problem, for the most part the voice cutouts/half a second of silence occur when the jitter or ping gets really high near the end of the cogentco.com network.

The program I used is from here (free 30 day trial):
http://www.pingplotter.com/download.html
Direct download link:
http://www.pingplotter.com/downloads/pngplt_pro.exe

Just do File -> Save Image...
to get a screen capture of the graph.


Brent

[laurent]

Yikes, that's a lot of hops!

I have the luxury of a small ISP that shares the same torix as FPL, therefore:

Code: Select all

traceroute to voip.freephoneline.ca (208.65.240.142), 64 hops max, 52 byte packets
 1  unknown (192.168.0.199)  1.673 ms  1.090 ms  0.910 ms
 2  lo-100.erx03.tor.packetflow.ca (206.248.154.101)  27.335 ms  21.263 ms  22.148 ms
 3  2110.ae0.bdr01.tor.packetflow.ca (69.196.136.34)  30.935 ms  20.604 ms  20.580 ms
 4  gw-295ca.torontointernetxchange.net (198.32.245.78)  21.530 ms  21.936 ms  20.816 ms
 5  host-208-65-240-142.static.295.ca (208.65.240.142)  32.660 ms  21.491 ms  20.640 ms

However, several hops is not necessarily a problem if packets are forwarded over there quickly.

You graphic shows that the time between your machine and FPL's server is between 26 and 45 miliseconds, which is very good. Barely more than me and I'm practically sitting a few inches from them.

But I'll let the experts at FPL chip in on this.

[zedsdead]

I noticed this the other day out of the blue, never happened before. My ISP peers with 295.ca at TORIX so it's never touching Cogent or any transit in general. My gf made a call just afterwards and she said it sounded fine however. I have a PAP2T, for what it's worth.

[tony_qc]

have the same problem with 2 house, 2 pap2t, 2 different router, 2 different connection (adsl and cable).

tryed all combinaison with the same problem....
all i can see, its a pap2t problems

[westalex]

Same problem here and I use the PAP2T. Does anybody have any update on this?

[tbrummell]

Interesting. I have an Asterisk server with IP phones and a PAP2. I almost 100% use a Mitel or Polycom IP set, never have a sound quality issue. The wife almost 100% uses the PAP2, complains of drop outs all the time. Time to wire the rest of the house and get the other IP sets plugged in I guess!

[beverly]

FPL

MJ

Gizmo5

Anyone else on Rogers going through this?

Do you download madly (Newsgroups/torrents)?
What kind of connection/modem (Which Docsis are you on DOCSIS 1.1, DOCSIS 2.0, DOCSIS 3.0?)?

I know I download madly on SB5100 Docsis 2.0 1up/10down
I just might give rogers a call with a piece of my mind.

[brentw]

So the problem appears to be with the PAP2, not with Rogers.
I took mine and tested it on two other connections, a Cogeco cable in Niagara and a Bell DSL in Toronto.
Both had the exact same problem that I experience at home on Rogers.
I have 3 other PAP2's setup at different houses all have the same issue.
I have a spare PAP2 that I reset fo factory defaults.
Just entered the login info for FPL.
Put it directly connected to the modem and the issue still happened.
So it's not even a setting that I changed in the PAP2.

I wonder if it is a problem specifically with the PAP2T 5.1.6 firmware.

FPL, can you confirm if you are using a PAP2T with 5.1.6 and no problems??

It's very strange that there were no issues with this firmware on the old FPL server, just with the new it appears.
I have been using this same PAP2 with the same firmware on FPL for about a year now and there were no issues until the new server.

FPL can you ask the programmers to investigate if there are any reported issues with your server software and PAP2T with 5.1.6?
Also, can you confirm what firmware is on your PAP2T that you use to test?

[FONGO_steve]

The Linksys PAP2T's do appear to be having some audio drop outs when call-waiting is in use. We are investigating the cause of this since no apparent changes were noticed in call waiting between the new server and the old server. It doesn't appear to affect all PAP2Ts so we are also seeing if we can narrow down what firmware this is affecting to duplicate it.

If I need any specific call examples I may message one or two of you having the problems - it's always nice to get some examples from outside a test lab for some of these problems too.

[brentw]

Thanks for the update Steve.

I can confirm the issue happens when there is no call waiting in use.
I do a fresh power cycle, imediately dial into voicemail, and within a few seconds of listening to the girls voice will have the sound drop for a split second.
So I don't think it is related to call waiting.

I just tried downgrading one of my PAP2T's but could only find 5.1.5, confirmed that the issue is the same as on 5.1.6.
And again, I did a reset to factory defaults and only entered Proxy, Display Name, User ID and Password.
Didn't touch anything else and it still happens.
So it doesn't appear to be a setting change in the PAP2T.

Let me know if you would like anymore details.
This is quite frustrating, I can't count how many times people have said "oh is that your call waiting?" and I have to say, not it's just my phone screwing up and cutting out for a split second.

Please keep us updated.

[mitwtim]

I am glad to see that other people are now reporting the voice-cut out issue. Steve, I am not sure what you meant about it being related to call-waiting, but from all of the testing I and my wife have been doing with it the last few weeks the only connection to call-waiting is that the symptoms sound like your voice is being interupted by a call-waiting beep. But, the sound cuts out when you are on one call and I can't remember any time where an actual call-waiting beep was coming through. Hope that helps.

Also, I am not sure how severe it is for the other people here, but I know for us it can happen several times per minute which is why this problem is having such a serious impact on our ability to use our phone. If it was once every 10 minutes or so, that would still be annoying, but not as urgent an issue - for us.

Any progress you can make would be GREATLY appreciated. Thanks!

[beverly]

Its definitely not just local to the PAP's. It also occurs on the SPA and X-Lite.

[FONGO_steve]

So far we haven't been able to duplicate this on any PAP2T or Grandstream ATA in the office. Multiple firmware versions have also been tested on both as well.

What other common trends are there amongst those of you who are having this issue? ISP or geographical region perhaps?