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ctaranto
02-16-2010, 10:01 AM
I've had a long standing issue with VoIP in general that I hope can be addressed.

I've been with Vonage (2 years), VoicePulse (3 years), and now VOIPo. On all three, I've notice that it's not really a full duplex conversation (ie. both parties talking at the same time, and both hearing at the same time). What we've experienced with VoIP is that the person talking to us always overrides what we're saying, so they can't hear us when they're talking, and we need to repeat what we said when they stop.

In contrast, when using our mobile phones, this isn't the case at all, so it's not a matter of who we're talking to. It's a real issue.

Any thoughts on how to resolve this (if it can be)?

Comcast ISP -> Motorola SB5120 -> DLink DGL-4100 -> PAP2T

I've used a WRT54GL running both Tomato and DD-WRT instead of the 4100, but it didn't make any difference in this issue. Also had an RT31P2. No difference. Also had various devices when with Vonage. No difference.

Thanks,

-Craig

sr98user
02-16-2010, 03:12 PM
I had a similar issue in the past. I finally found out that it was due to the Panasonic cordless phone. I don't have the model number handy. It was an older model. Try to use a different phone and see if it fixes the problem.

ctaranto
02-16-2010, 07:53 PM
I had a similar issue in the past. I finally found out that it was due to the Panasonic cordless phone. I don't have the model number handy. It was an older model. Try to use a different phone and see if it fixes the problem.

Interesting. I also use a Panasonic cordless phone (in particular, this one (http://tinyurl.com/ycv67wc)). I don't think I had it while we had POTS, so I can't compare how it used to be.

What did you replace yours with?

-Craig

fergessen
02-16-2010, 09:57 PM
I too had the same problem, but on Broadvoice though.

I too had Panasonic 5.8ghz cordless phones.

On a hunch/splurge, I replaced it with a Panasonic four handset DECT version.

I do not notice the problem any longer. (Now on VOIPo.)

Interesting to note; you will not find this limitation (or improvement) in the Panasonic literature or any review online. Odd.

sr98user
02-17-2010, 07:12 AM
The problem one is KX-TG5433 (5.8 GHz).

Now I use KX-TG1031B (DECT 6.0). Actually I still use the other one on Line2.

ctaranto
02-17-2010, 09:36 AM
Thanks for the info. Just ordered this (http://www.amazon.com/Panasonic-Handset-Cordless-Answering-KX-TG1034S/dp/B000LYCUF8/ref=sr_1_1?ie=UTF8&s=electronics&qid=1266420918&sr=8-1).

If this solves the problem, I'll be none too happy that we've been "suffering" with half duplex for years. :)

-Craig

ctaranto
02-17-2010, 09:50 AM
I too had the same problem, but on Broadvoice though.

I too had Panasonic 5.8ghz cordless phones.

On a hunch/splurge, I replaced it with a Panasonic four handset DECT version.

I do not notice the problem any longer. (Now on VOIPo.)

Interesting to note; you will not find this limitation (or improvement) in the Panasonic literature or any review online. Odd.

I also find it odd that there's no mention of this issue on the 5.8Ghz Panasonic phones. I'm sure they sold millions of them, and for not one person to blog about it is unexpected.

-Craig

patoka
02-17-2010, 10:38 AM
I have a KXTGA545 that doesn't always send zeroes from the keypad, both it and my 6700 have the half duplex problem as well.

ctaranto
02-17-2010, 11:27 AM
I have a KXTGA545 that doesn't always send zeroes from the keypad, both it and my 6700 have the half duplex problem as well.

Appears the 6700 line is a 5.8Ghz unit as well. Maybe all Panasonic 5.8Ghz phones have this issue?

-Craig

MisterEd
02-17-2010, 02:41 PM
I have an RCA Dect 6, 2-Line phone, same problem. Had it with Vonage as well as Voipo. Bad thing is, when my wife is talking I can't shut her up because she doesn't hear me (unless she pauses to breath which is rare). :)

holmes4
02-17-2010, 03:48 PM
Interesting - I also have Panasonic 5.8GHz phones and had not really noticed this as an issue, but it might explain some things...

usa2k
02-17-2010, 04:35 PM
The day before this discussion started, I was talking to my Brother In-law in OH (and I am in MI.) We experienced that half duplex effect and thought it could be the cheap phone he used. I never did ask what kind of phone it was though. At the time, he had called my cell phone (AT&T).
Call Reference ID: 508b90b5-2241db7e@75.13.38.39
I called him back today from my VOIPo account a moment ago to the Reseller account he was helping me test, and these two phones had perfect duplex operation. That leaves me thinking that some codec issue created the half duplex effect.
Call Reference ID: e4d9a638-5e912206@192.168.0.73
My phone BTW is a UNIDEN 2-Line 5.8 Ghz TRU 9466.
Our calls always feel like full duplex from the VOIPo PAP2T/Uniden.

usa2k
02-23-2010, 09:03 PM
FWIW from an ATA configuration perspective ....

http://www.dslreports.com/forum/r22206195-VOIP-the-sensation-of-halfduplex-conversations-

http://www.dslreports.com/forum/r22431755-Distorted-sound-when-talking-simultaneously

These references seem to key in on Echo Suppression on the ATA:

Re: Distorted sound when talking simultaneously

I'd say we're probably talking about an issue of perception here. Echo suppression is essentially just a speech gated automatic partial half-duplex. I say partial, because it doesn't fully turn off speech in the opposite direction; it just reduces its level by some 30 dB. This enforced half duplex lasts for some time delay after the speech ends, which coincides with the 1 to 2 seconds of "distortion" that you describe. It's the only voice feature in ATAs that behaves in this manner. Although it just reduces the volume, but not in and of itself distorts it, you may perhaps be perceiving the unexpected reduced volume as distortion. Technically, though, at the lower level, the speech will be more distorted due to lesser sampling accuracy. Now, if your phone has an AGC feature that amplifies the muted speech back to normal levels, it will of course sound more distorted.

Not to say it is this. Just adding more areas of speculation.
DogFace05 in the above quote is a very savvy person.

lifespeed
10-24-2010, 01:52 PM
I have an RCA Dect 6, 2-Line phone, same problem. Had it with Vonage as well as Voipo. Bad thing is, when my wife is talking I can't shut her up because she doesn't hear me (unless she pauses to breath which is rare). :)

ROTFL! :rolleyes:

lifespeed
10-24-2010, 01:57 PM
Yes, echo cancellation implemented in an ATA with an analog phone is a likely culprit. The silver bullet solution is to switch to a real IP phone (plugs into ethernet) instead of an ATA. See my post here (http://forums.voipo.com/showpost.php?p=20137&postcount=18)on the same subject.