Analog trunks hanging on call status CLEARING for days

[g18c]

Dear all, I have analog trunks which are hanging on call state CALL CLEARING when hanging up incoming calls (outbound calls are not affected).

I have tried different locales and also disabling disconnect clear and tweaking disconnect clear values (100, 350, 500), same issue.

There are two ATMv2 combo cards in this box, it does the same on all 8 trunk lines from the ISP.

I plugged a normal analog handset in to the ISP trunk lines, and it rings ok and stops ringing when i stop ringing it. Unfortunately this is likely the same test the ISP will do to "prove" their line is ok - i understand there is some signaling that the human ear cannot hear that may not be getting sent.

I have tried firmware 8.1.79 and 8.1.81, including re-creating the SD CARD.

Any ideas what i could try next or is this likely a ISP issue?

 

[g18c]

Uploaded image from IPO Status here:

http://postimg.org/image/g9vlq6ol7/

 

[g18c]

Sorry reuploaded here:

http://s28.postimg.org/9d397di4t/clearing.jpg

 

[hairlessupportmonkey]

You will have to tweak the disconnect clear timer

ACSS - SME
General Geek

 

[amriddle01]

He has, but it's not much use if the provider doesn't have it turned on, make sure they have and ask them what the timer is set at. Also turn on busy tone detection in the meantime (reboot required) as that usually sorts things like this out

 

[g18c]

Thanks for the replies hairlesssupportmonkey and amriddle01, i tweaked the disconnect clear, and also more worryingly i setup busy tone detection (system frequency) and it still hangs.

Sometimes when i dial in the call is answered and i hear a fax type noise for a second followed by silence for a couple of seconds and then disconnects, but IP Office doesn't show any call alerting on the trunk.

 

[amriddle01]

Sounds like emulated lines rather than true analogue trunk lines, and whatever they're using to do this isn't very good

 

[g18c]

Yup well this is still going on.

The awesome ISP here just come along and plug their 3 quid analog phone and grin showing it working.

They do not have the mental capacity to understand about frequencies or cadence settings.

I have found out they are using a 425Hz busy signal - on IP Office i can only set the telephony frequency settings to 420Hz or 430Hz... any idea how i can set it to this specific value?

This has been going on for a week now, next step will be to provide completely new unit and trunk cards, and if that fails will just take out the kit and give a full refund.

 

[mattKnight]

Are they providing a copper pait with DT or a demarc device?

If its a device, are there any model numbers etc?

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.

 

[mforrence]

@g18c - where on the globe are you located? In North America, standard disconnect supervision is a 450ms break in loop current. Easy to test with a butt set and analog multimeter - with your butt set connected at NID, and multimeter across tip/ring set on DCV, call someone and ask them to hang up on you. If disconnect is being sent by carrier, you'll see meter dip to 0V for half a second. No dip = no disconnect signal. This is a common trouble with non-ILEC carriers - hardest part is explaining to them that you need Bellcore standard disconnect supervision.

If you're not in North America, please disregard as I have no idea how other areas work.

 

[g18c]

Specifically they are using a Mediatrix analog trunk box.

I have used other Mediatrix boxes they provided at other sites, and not had any issues.

I don't know if this is the same model/firmware as i cant get access to their comms rack, they provide me the lines over a short copper riser.

It is also intermittent, will be fine for a day, then lines will start hanging when far end disconnects first.

 

[mattKnight]

Assuming it is a C7 Series (plus many other mediatrix boxes too)

Send them this link (

http://wiki.media5corp.com/wiki/images/8/8e/MTX_Dgw_v2-0_SCG.pdf)

and point them at page 165. That page tells them what they need to do
(copy your customer too - so that they know where the blame is)

Sorted!

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.

 

[g18c]

Very informative, many thanks!

The only question i have now is - why would this be intermittent?

When testing today, i saw calls disconnect when i hung up remotely calling in to client site - no delay or hanging, it was bang on.

Then 8 hours later they are calling me complaining the lines have hung.

One thing i didnt test was 'prank' calling, i.e. calling and hanging up before anyone could answer - i don't know if that would cause lines to hang, in theory should just be a normal disconnect.

Any other reason this could be intermittent?

 

[amriddle01]

When a human hangs up so does the system as it knows the call has ended, when an AA or mailbox answers or they hang up while it's alerting it has no way to know that unless it's given a signal to that effect, so basically disconnect clear or hearing a tone at the programmed frequency

 

[mattKnight]

Usually disconnect clear issues get highligjted by auto attendant or voicemail usage.

Usually users are smart enough to realise that the remote end has gone away - thay get bored after about 15 or 20 seconds of silence and hang up too

Try leaving a voicemail and see if the lines hang

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.

 

[g18c]

I have some more info, appreciate all the help people have given so far:

1) If i dial in, and they answer and either party hangs up, it disconnects OK

2) If they dial out to me, and I answer and either party hangs up, it disconnects OK

3) If i dial in, see their trunk show CALL ALERTING, I then hangup, their trunk continues to call alert and rings the extensions. Once a user picks up, status shows CONNECTED but of course they cant hear anyone (as i already hang up)... they then put down the phone and then the line hangs in CLEARING state.

So specifically, this only happens if calls come in, RING is trigged on the trunk and for whatever reason person calling in hangs up before it is answered, the line then gets hung.

Seems to me ISP is sending a RING START signal but not a STOP RINGING signal when the person hangs up before it was answered.

Does this shed light on a deeper issue? Anything I can try to fix? Still only an ISP issue?

ISP are useless, just obsessed about testing this with an analog phone.

 

[Telecomboy]

Disconnect clear is the answer. They don't seem to be providing it.

 

[amriddle01]

Seems to me ISP is sending a RING START signal but not a STOP RINGING signal when the person hangs up before it was answered.

Analogue trunks have no signalling that's what causes this issue (with many systems, not just IPO), it's also why disconnect clear was devised

 

[g18c]

Thanks for all the replies - compared to PRI, analog lines are an absolute nightmare and often require a number of follow up visits after install - time to review our installation price for analog trunks methinks!