Caller ID and poor sound quality

[Philip Ellis]

I've got a Grandstream HT-503 that I use as a gateway between my PSTN and my internal 3CX system.

1) I'm not happy with the sound quality of calls via the HT-503. What I don't know is if it is possible to tweak some settings that will help or if it is just-the-way-it-is. Any clues, anyone?

2) When receiving calls I don't get the caller's ID coming through. I just get the SIP id of the HT-503 which is 10000. I've examined the packets coming from it to the PBX and they've got 10000@<ip address> in them. I've search the web for appropriate settings to make it work but nothing has worked, so far. Does anyone here have a HT-503 (or similar) that they've got caller id working with on a UK line? The line is operated by Zen Internet - I don't know if that makes a difference vs. British Telecom. My current settings are below:



Thanks.

 

[leejor]

I would speak to your provider about the type of Caller ID that they use. I have heard that some UK providers make use of non-BT types. You could test with a stand-alone UK Caller ID box.

As far as sound quality, what is the issue? Is it background noise, echo, choppy sound? Most ATA's do have different settings depending on where in the world they are used.

Did you come across this post...

https://community.plus.net/t5/Broad...tone-HT503-esp-Caller-ID-via-PSTN/td-p/713867

The settings used are a bit different from yours.

Yet this one is very similar...

http://www.coochey.net/?p=68

And Virgin seems to use the Bellcore type CID, if that is still current.

http://www.ewan.cc/?q=node/143

 

[Philip Ellis]

I would speak to your provider about the type of Caller ID that they use. I have heard that some UK providers make use of non-BT types. You could test with a stand-alone UK Caller ID box.

As far as sound quality, what is the issue? Is it background noise, echo, choppy sound? Most ATA's do have different settings depending on where in the world they are used.

Did you come across this post...

https://community.plus.net/t5/Broad...tone-HT503-esp-Caller-ID-via-PSTN/td-p/713867

The settings used are a bit different from yours.

Yet this one is very similar...

http://www.coochey.net/?p=68

And Virgin seems to use the Bellcore type CID, if that is still current.

http://www.ewan.cc/?q=node/143

I'm with Zen and I spoke to customer support. They were a bit vague, to be honest, but I eventually was told that they use all BT equipment so I'm assuming SIN 227 for now.

Re. the link to Plusnet, since they are BT-owned I hope that the settings will be the same as Zen so I'll follow that document through.

The sound quality issue is because of background noise - it's like holding a seashell to your ear. It's not massively intrusive but is there all the time. I've not experienced any choppiness or echo.

My most frustrating issue right now is definitely the CLI. There are SO many variables!

 

[leejor]

Background noise (a hiss?) doesn't sound (no pun intended) like a SIP issue, rather, a PSTN line setting issue. I've worked with the Cisco/linksys ATA's and i know that to get the sound quality "just right" requires some changes from the North American "default" settings, when used in the UK. Capacitance. impedance, and the like.

Have you confirmed that DID works using a stand-alone CID box (borrow one if you have to, or buy one, then return it)? If that doesn't even work, you might same yourself a lot of time trying to get something working, that won't.

This is an interesting read on the subject...

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

 

[Philip Ellis]

Background noise (a hiss?) doesn't sound (no pun intended) like a SIP issue, rather, a PSTN line setting issue. I've worked with the Cisco/linksys ATA's and i know that to get the sound quality "just right" requires some changes from the North American "default" settings, when used in the UK. Capacitance. impedance, and the like.

Have you confirmed that DID works using a stand-alone CID box (borrow one if you have to, or buy one, then return it)? If that doesn't even work, you might same yourself a lot of time trying to get something working, that won't.

Thanks for the heads-up on the hiss. Sounds (no further pun intended!) like I've got some playing about to do.
Once I'm happy that I'm doing the right thing with the whole VoIP thing I'm tempted to buy a gateway that is certified with 3CX.
My only concern is that they're kind of more than I need (e.g. I only need one FXO port) and, therefore, are relatively expensive, certainly compared to the HT-503 that I've got now.

I know that CID works because my existing phones which are also plugged into the PSTN show numbers with no problem.
I had intended to have a mess around with the settings in the HT-503 today but events overtook me and I've been unable to.

 

[complex1]

Hi,

Please check the Inbound Parameters Variable and SIP Field with next settings to get a working CLI.
DevHostPort -> Contact : Host Part
CalledName -> To : DisplayName
CalledNum -> To : UserPart
CallerName -> From : DisplayName
CallerNum -> From : UserPart

 

[leejor]

One thing to check...on UK CID, I believe that a current reversal proceeds the call, to wake up the unit, which would lead me to believe that any device that can receive it, may be polarity sensitive. You might want to check the wiring/polarity to the gateway socket.

As far as gateways are concerned, I'm nor certain that there is going to be anything less that one with two FXO ports (which will also have two FXS ports), available. Keep an eye open for a SPA-3102. They have been discontinued and have become hard to find, but they are a great unit (were supported at one time, but still work) and do show up at flea markets and Craigs List once in a while. You want an unlocked one.

 

[Philip Ellis]

Hi,

Please check the Inbound Parameters Variable and SIP Field with next settings to get a working CLI.
DevHostPort -> Contact : Host Part
CalledName -> To : DisplayName
CalledNum -> To : UserPart
CallerName -> From : DisplayName
CallerNum -> From : UserPart

Hi

Those are the settings that I have. However, I believe the problem is my gateway.
Using tshark I can see the that gateway is sending "10000@<ip address>" to 3CX as the ID so that's all the PBX sees.
This is confirmed as I see the caller ID as 10000 when I receive an incoming call.

My problem is getting the settings on my Gateway HT-503 correct so that it picks up the CID.

 

[Philip Ellis]

One thing to check...on UK CID, I believe that a current reversal proceeds the call, to wake up the unit, which would lead me to believe that any device that can receive it, may be polarity sensitive. You might want to check the wiring/polarity to the gateway socket.

As far as gateways are concerned, I'm nor certain that there is going to be anything less that one with two FXO ports (which will also have two FXS ports), available. Keep an eye open for a SPA-3102. They have been discontinued and have become hard to find, but they are a great unit (were supported at one time, but still work) and do show up at flea markets and Craigs List once in a while. You want an unlocked one.

I can check the socket with one of my old phones that does show the CID. I strongly suspect that it will be OK but you never know.
In the gateway parameters I've got CID scheme set as "SIN 227 - BT" - I'd have thought that this would take account of current reversal.
I've been poking around some of the xml config files that 3CX supply for the supported gateways and at least one of them mentions ETSI with regard to the UK. The gateway has a couple of scheme options that mention LR which means, I think, Line Reversal and I'm guessing this is the same as current reversal. I think my next stop is to give those options a whirl.

I've spotted that the SPA-3102 is/was quite popular as an entry-level device but haven't been able to find one so far. I'll have another look, though. The HT-503 offers a bewildering array of settings - maybe the 3102 is a bit simpler!

Thanks.

 

[leejor]

The HT-503 offers a bewildering array of settings - maybe the 3102 is a bit simpler!

Most people would say the opposite. The 3102 has many more functions/options, and can be quite intimidating to those unfamiliar. For use as a 3CX trunk, there are only a certain number of parameters that need to be changed, in most installations. 3CX used to have a manual set-up guide page, but that, unfortunately, disappeared when the device was no longer "officially" supported. You best bet is to find someone in the UK that uses the Grandstream device, to mirror the settings. The GS forum might be a good place to post a query if you haven't done so.

 

[Philip Ellis]

Most people would say the opposite. The 3102 has many more functions/options, and can be quite intimidating to those unfamiliar. For use as a 3CX trunk, there are only a certain number of parameters that need to be changed, in most installations. 3CX used to have a manual set-up guide page, but that, unfortunately, disappeared when the device was no longer "officially" supported. You best bet is to find someone in the UK that uses the Grandstream device, to mirror the settings. The GS forum might be a god place to post a query if you haven't done so.

I've had another look for a 3102 but no luck, unfortunately!
Agree that the GS forum is probably the best place to find a kindred spirit

 

[Philip Ellis]

Great news - I've got caller id working!!!

I set up syslog and could see that the HT-503 was picking up the calling number.
The trick was to get that number over to 3CX.
On the "FXO PORT" page, I changed the "Tel URI" fields to "Enabled" and it all works

Just the background hiss to sort out now...

 

[leejor]

As far as the hiss...Since you can also plug a telephone into 503, you might want to see if there is also a hiss on the handset, with, and without the phone line plugged in (is it the phone line interface actually causing this ?). Besides the phone line settings, the power supply and/or a faulty component (capacitor?), while unlikely, could be to blame.

Also check that firmware is up to date.

At the bottom of page 74 of the manual

http://www.grandstream.com/sites/default/files/Resources/ht503_user_manual.pdf

there appears to be the settings applicable to the country the device is to be used in. (not including the Number of Rings)

You would have to do some searches for correct settings, or experimentation, to see what works for you.