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Static heard on all Google Voice calls on OBi202

Started by LotharX, March 08, 2017, 12:21:13 PM

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LotharX

I have a new OBi202 that I bought 3 weeks ago, that I have been using with Google Voice.  I have been disappointed with the voice quality on all of the calls (either incoming or outgoing) that I've been making on that device.

The problem is that there is a faint static-y or "buzzy" quality to what I hear when I am on a call.  The best way I can describe it is that the voice quality sounds electronic, not natural like a landline phone should sound.  I am not experiencing any delays or choppy sound though.

The dial tone sounds very clear--it's just the person's voice that is static-y.

I have a Panasonic KX-TGE470 cordless landline phone plugged into the OBi202's Phone1 port.  This is a very high-rated telephone that is supposed to have excellent voice quality.

To rule out the telephone as being the problem though, I later went and bought a cheap AT&T TR1909 corded phone, and plugged it into the OBi202's Phone2 port (leaving the Panasonic phone plugged into the Phone1 port).

The call quality is slightly better on the AT&T phone, but I can still hear the static-y quality of voice call.  It's just not quite as pronounced as with the Panasonic phone.

With either phone, the subtle static is enough to make the phone calls slightly annoying.  The voice quality is better when using my smartphone to make calls, and I've never been that impressed with my smartphone's voice quality.  The whole reason why I bought the OBi202 is so that I wouldn't have to use my smartphone inside the house.

My OBi202 is plugged directly into my router, an Asus RT-AC68U, via a cat6 ethernet cable.

I've played around with the QoS settings in my router, trying various ways to assign highest priority to the OBi202, but nothing has helped.

I've attached test results I ran today from Phonepower.com.  I tried running the test first using a laptop computer via a 5.0 GHz WiFi connection that consistently gives me 300 Mbps download / 30 Mbps upload speeds, using Comcast's speed test website. 

Then I ran the test using another laptop computer via an ethernet connection.  The latter computer doesn't have a great network card in it, and is always far slower than my WiFi connection on the other laptop (weird, I know).

The attached results are from the WiFi-connected laptop. 

When I re-ran the test using the Ethernet-connected laptop, the results were similar, but with a slightly lower Estimated MOS score of 4.0 (vs. 4.2 over WiFi), but a somewhat higher Download Consistency of Service of 49% (vs. 34% over WiFi).  On either the WiFi or the Ethernet computer, the test returned green (acceptable) icons for all of the summary test areas.

Any suggestions would be most appreciated!

drgeoff

Dial **9 222 222 222 and listen to the announcement from 'Obiman'.  How does he sound compared to the voices on your incoming calls?

Your stats are all good and would have no influence on voice quality?

SteveInWA

Hi, and welcome to OBi-land!

Typically, the kind of noise you are hearing is unrelated to your internet connection's quality, unless the quality is really bad (below MOS 3.5 or so).  Think of it like HDTV or HD Radio:  it sounds and looks perfect, until it seriously degrades and/or quits completely.

It's more likely to be coming from your cordless phone, or some nearby electronic equipment, or, rarely, from a bad 12V power supply (the "wall wart").

You said that you tried a corded phone, but you left the cordless attached.  Try completely unplugging the cordless phone base station's power brick, and unplug its phone cord from the OBi.  Then, try some calls with only the corded phone plugged in.  You can also try relocating the OBi a few meters away from whatever else is now next to it.  Occasionally, people put the cordless phone base station right on top of, or right next to the OBi and/or their router, which can inject noise, too.  Don't do that.

To bypass Google Voice, try calling the OBi echo test number **9 222 222 222 and listen for the noise.

Google Voice uses the G.711u PCM CODEC, on the "leg" between your OBi and their servers, which is lossless and should sound better than the best copper telephone line.  There are other carriers in the call path.  Sometimes, those carriers will start out the connection using a lower-quality CODEC, e.g. G.729, and then negotiate up to G.711 after a few seconds or more.  In those cases, you may hear distortion for a while, and then it gets better.  Try calling different locations around the country, (e.g. friends or numbers like the library or city hall or a local grocery store), and see if the call quality varies.

LotharX

Thanks very much for the suggestions, guys.

I originally had my OBi202 inside a stereo system cabinet that has a lot of stereo components in it (though they have all been powered off while making phone calls).  The cordless phone's base station was sitting on a different shelf in that cabinet.  Both units were plugged into the same power strip, which had a lot of other things plugged into it.

So today I tried using a longer Ethernet cable, so that I could move both units to the opposite end of the room, about 12 feet away.  I then plugged both units into a different wall outlet that has nothing else plugged into it.  I then tried plugging in each phone--the cordless and the corded--into the OBi202 (separately, one at a time), and calling the OBi echo test number.

I made sure the cordless phone was unplugged--both from its power brick and from the OBi202--before trying the corded phone, as you suggested.

With the cordless phone, I still hear that static, and it's just as pronounced.  I'm trying to think of a better way to describe the noise--it's not exactly static, but sort of a "scratchy" quality to the sound.  It's very annoying.

Then I tried the corded phone.  The sound is much clearer than with the cordless phone (like it was before, when it was located inside the stereo cabinet), but I do hear a sort of very faint screeching sound in the background behind "OBi Man's" voice.  I am curious if any of you can tell me if that is what you hear on your own phones, or if you instead hear dead silence in the background, in between his words?

Returning the cordless phone to Amazon, to try exchanging it for a different model, will be a pain, so I don't want to do that until we rule out anything else that could be the cause of the problem.

I'm wondering if the noise is actually present on both the corded and the cordless phones, but the cordless phone is somehow amplifying the noise so that it is more perceptible on that phone?

Any other suggestions would be appreciated!

drgeoff

Dial **0 and let it ring until the Auto Attendant ('Obiwoman') answers.  How does she sound on your two handsets?  I hear less background "noise" on her than him.

You may be able to mitigate the static by reducing the level of the audio signal sent from the 202 to the handset.  Physical Interfaces, Phone1 (or 2) Port, Port Settings, ChannelTxGain.  Reducing the value there (more negative if already negative) gives lower volume from the handset earpiece

azrobert

You can call the other Phone Port by dialing "#". This will eliminate any problem caused by the network.

LotharX

Quote from: drgeoff on March 09, 2017, 10:06:38 AM
Dial **0 and let it ring until the Auto Attendant ('Obiwoman') answers.  How does she sound on your two handsets?  I hear less background "noise" on her than him.

You may be able to mitigate the static by reducing the level of the audio signal sent from the 202 to the handset.  Physical Interfaces, Phone1 (or 2) Port, Port Settings, ChannelTxGain.  Reducing the value there (more negative if already negative) gives lower volume from the handset earpiece

Thanks drgeoff, I tried your suggestions.

Calling that **0 number did result in less background noise (almost none), and OBiwoman's voice sounded a lot less scratchy than OBiman's voice did on the echo test number.  The scratchy quality is still there, but barely perceptible.

Calling **0 using the corded phone sounds a bit better.  It sounds very good actually, but not perfect.

I found the ChannelTxGain setting that you mentioned, in the advanced section of the web-based dashboard.  It will not allow me to change the default value (-5).  In fact, there is no setting on that entire page that I am able to change.  The only things that can be changed on that page are selecting either of the two checkboxes next to each setting ("Device Default" or "OBiTalk Settings").

Changing the checkbox for that particular setting changes the setting from -5 to -2.  So those are the only two values possible for that setting, unless I am missing something.

There are red exclamation point icons to the right of both the ChannelTxGain and ChannelRxGain fields.  None of the other settings on that page show that icon.  What does that mean?

I tried the -2 setting, just out of curiosity, and when I then tried to call the echo test number, I heard a very loud buzz, then it disconnected the call (before I even heard OBiman's voice), and then it went back to dial tone.  I then tried the echo test again, and this time it connected.  I heard his voice, with the same scratchy sound quality, sounding no different than on the -5 setting.

So I changed it back to -5, called Obiman again, and once again I heard the loud buzz and then back to the dial tone.  I then tried Obiman again and this time it went through (with the same scratchiness).

I'd be very interested in trying a lower (more negative) setting, if there is a way to specify a particular value.

drgeoff

You need to have both boxes unticked at the right hand end of the line before you can change the value for that line.  You can put any integer values between 6 and -12 in those gain fields.  Tx controls volume heard by you.  Rx controls level of what the OBi receives from your microphone and sends to the other end of the call.

The red exclamation marks merely indicate that the values are no longer the default ones.

LotharX

Quote from: azrobert on March 09, 2017, 10:50:09 AM
You can call the other Phone Port by dialing "#". This will eliminate any problem caused by the network.

Excellent suggestion, thanks!

I tried that, and the sound quality through the receiver of the cordless phone (while speaking into the microphone of the corded phone) sounds very good.  It wasn't perfect, but I didn't notice any substantial scratchiness.  

It was rather hard to evaluate though, because the sound of my voice coming out of my mouth made it hard to isolate the sound of my voice coming out of the phone.  So I was hearing my voice from two different places (live vs. transmitted), if that makes sense.

drgeoff

#9
When you click submit the portal will download the settings to your OBi and the OBi will then reboot.  It was probably that reboot that interrupted your test call and gave you dial tone again when the reboot completed.

The Admin Guide (http://www.obihai.com/OBiDeviceAdminGuide) says the gain values can be 12 to -12 and the defaults are both 0.

LotharX

Quote from: drgeoff on March 09, 2017, 11:05:51 AM
You need to have both boxes unticked at the right hand end of the line before you can change the value for that line.  You can put any integer values between 6 and -12 in those gain fields.  Tx controls volume heard by you.  Rx controls level of what the OBi receives from your microphone and sends to the other end of the call.

The red exclamation marks merely indicate that the values are no longer the default ones.

Ah, great, that's what I was missing, thanks.  

Okay, I was now able to change the Tx setting all the way down to the minimum value of -12 (I also tried -10).  I still hear the same scratchiness on OBiman.

Also, the exclamation points were there before I even starting playing around with the settings.  I never changed the Rx setting at all (and didn't touch its checkboxes), and that field has an exclamation point.  Does that mean anything significant?

drgeoff

Quote from: LotharX on March 09, 2017, 11:16:21 AMI never changed the Rx setting at all (and didn't touch its checkboxes), and that field has an exclamation point.  Does that mean anything significant?
That is strange and as per my edit to previous post the defaults are 0.

LotharX

Quote from: drgeoff on March 09, 2017, 11:19:04 AM
Quote from: LotharX on March 09, 2017, 11:16:21 AMI never changed the Rx setting at all (and didn't touch its checkboxes), and that field has an exclamation point.  Does that mean anything significant?
That is strange and as per my edit to previous post the defaults are 0.

Very odd.  The defaults I saw for Tx and Rx were -5 and -4, respectively. 

Could those values have gotten changed automatically, in response to some detected problem with the connection?

azrobert

Quote from: LotharX on March 09, 2017, 11:08:00 AM
It was rather hard to evaluate though, because the sound of my voice coming out of my mouth made it hard to isolate the sound of my voice coming out of the phone.  So I was hearing my voice from two different places (live vs. transmitted), if that makes sense.

You can put one handset by a TV or stereo. It might sound like you're in a tunnel, but you should be able to hear the scratchiness. It would be better to get another body on the other handset. I forgot to suggest unplugging the OBi202 from the network before testing.

LotharX

#14
Quote from: azrobert on March 09, 2017, 11:51:51 AMYou can put one handset by a TV or stereo. It might sound like you're in a tunnel, but you should be able to hear the scratchiness. It would be better to get another body on the other handset. I forgot to suggest unplugging the OBi202 from the network before testing.

Great idea.  I tried that using my home audio system, which is a surround 5.1 system.  I set down the microphone of the corded phone right in front of the center channel speaker, then set the system to TV, and turned the stereo receiver's volume down to a level that approximated normal speech.  I disconnected the Ethernet cable from the OBi202 (which I did do earlier, but thanks for mentioning that), and then dialed **0 so I could pick up on my cordless phone.

Then I took the cordless handset into a room where I could not hear the stereo speakers at all.

The sound was somewhat electronic, not like listening to a live human, but it was good enough so that I couldn't discern any scratchiness.

I then got the idea to reconnect the OBi202 to the network, then call a business I know that has an automated attendant answer the line (using the cordless phone).  That sound was very clear.

What seems to be happening is that anytime I call a phone that has any sort of line noise (like calling somebody's cell phone, or calling somebody who doesn't have a very good telephone, or calling OBiman), the noise is getting "mixed into" the voice transmission, for lack of a better way to describe it.  It causes the voice to become very scratchy and extremely annoying--bad enough so that I have a hard time understanding the whole conversation.  If the other party has a crystal-clear telephone, then I don't hear the scratchiness.

So we're back to the question of how to fix it?  Is there any other setting in the OBi202's dashboard that would be worth experimenting with?

LotharX

UPDATE:  I bought another brand of cordless phone today (an AT&T), just to find out if the cordless Panasonic phone was the problem.

The scratchiness is still there when calling OBiman on the echo test.  If anything, it's even worse on the new AT&T phone, but only when using its cordless handset.

The AT&T phone also has a corded handset on the base unit.  OBiman sounds fine (not great, but acceptable) on that handset.

So it seems that the problem is only pronounced with cordless handsets, no matter what brand of cordless phone I use.  Why would that be the case?  Does the OBi202 have some peculiarity that would cause noise over DECT 6.0 radio signals?

SteveInWA

Why do you expect that a cordless handset will sound as clear as a corded handset?  Even though modern DECT cordless phones use digital audio communications, it's still a radio, and it's going to introduce some noise.  Also, consider the price:  you're not buying an "audiophile" product when you buy an inexpensive cordless phone -- they've "value engineered" it down to the lowest possible manufacturing cost.

I think you are after unattainable perfection at that price point.

LotharX

Quote from: SteveInWA on March 10, 2017, 04:50:47 PM
Why do you expect that a cordless handset will sound as clear as a corded handset?  Even though modern DECT cordless phones use digital audio communications, it's still a radio, and it's going to introduce some noise.  Also, consider the price:  you're not buying an "audiophile" product when you buy an inexpensive cordless phone -- they've "value engineered" it down to the lowest possible manufacturing cost.

I think you are after unattainable perfection at that price point.

I've used cordless telephones before over POTS lines, and those were years before the technology that's available today.  I've never heard noise like this before.  If you could hear what I'm hearing, you'd understand... the noise is so bad that it's hard to understand the person I am speaking to at times. 

This goes way beyond the simple limitations of a cordless handset.  There's definitely some sort of problem with my connection.

I've also used cordless phones, with my old Comcast VoIP connection in my previous house, and it's always sounded crystal clear to me.

Just out of curiosity, if anybody reading this has a good-quality cordless phone, please try this test for me... disconnect the ethernet cable from your Obi, then dial ***4.  I am curious if the sound is reasonably clear, or if you hear any sort of distortion to OBiwoman's voice?

SteveInWA

That ***4 test is pretty meaningless.  The voice you are hearing is digitally-assembled and compressed, and yes, it sounds fuzzy.  The only valid test is to call another live human being on another telephone number and have a conversation.  Try a couple of different calls to different people who have some form of digital phone service (from their cable company or a quality VoIP service provider).

You can sign up for SIP VoIP phone service with one of the a la carte (no monthly plan) providers and compare their service to Google Voice.  A few bucks and an hour of your time for that test compared to days worth of posts so far could be a quick and useful comparison.

If you want to get esoteric about testing, you could find another 12VDC power adapter from some other gizmo you have laying around, and swap it for the one that came with the OBi.  Or, just give up and return or exchange the OBi.

I have a 202, a bunch of 200s that I manage for friends, a 1022 and a 1032.  I don't hear any unusual distortion in any of the calls.  I have an old Panasonic DECT 6.0 cordless phone and a cheap hardwired phone attached to the 202, and they sound fine to me.  FWIW, I settled on -3dB for ChannelTxGain and ChannelRxGain.  Overdriving the amplifier in the phone by setting the gain too high will cause distortion, and setting the gain too low will cause poor signal-to-noise ratio.  

Finally, you can look at your OBi's local web interface (access via the IP address, not via the OBiTALK web portal) during a phone call, under the Status-->Call Status section, and view the CODEC in use.  If it isn't G.711 after some potential re-negotiation up or down with G.729, then that would cause your symptom (G.729 can sound distorted and scratchy compared to G.711, which should sound like the best POTS call you've heard).  Don't make conclusions based on calling one number, as that number may have a sub-par call route.

LotharX

Thanks for that latest reply, Steve, that was particularly helpful.

I checked the CODEC during a call, and it is reading as G.711U for both Tx and Rx.

Shortly after I made that test, somebody happened to call my Google Voice number, and I picked up on my Panasonic cordless handset.  The call was so scratchy that I could barely understand anything that the caller was saying.  I probably understood maybe 60% of his words.  This is a really severe problem, and my OBi202 is now pretty much useless using a cordless telephone.

I'd be willing to entertain the possibility of buying a high-end business VoIP telephone, but it just doesn't seem to me that I should need to go to such an expense to get a decent cordless VoIP call quality.  My whole reason for buying the OBi202 (and using Google Voice) was to save some money on my telephone expenses.

I did contact OBi tech support via email yesterday about this issue.  They ran diagnostics and said that my "OBi is normal and the internet connectivity is good."

They said that some sort of wireless interference from some other device might make my OBi sound scratchy.  I have a whole lot of electronic devices in my house, including a lot of WiFi-enabled home automation devices, so if that's the issue, it could be anything.

They suggested that I try a cordless VTECH phone, saying that it should be working very well with the OBi.  I am wary of buying yet another cordless phone, but I will if we've ruled out everything else that I can try.  I see that VTECH has a line of phones that have "HD Audio," and am wondering if one of those would make any difference, since they apparently use a wider range of frequencies.

I did try playing around with various Channel TxGain settings, but nothing is helping.