Phantom 2nd Call

[newmarket25]

This building has 2 phone lines, 555-3334 and 555-3329. We were having some issues with 3334, so we told the phone company to catch any calls for 3334 and just route them to 3329.

When you call 3334, you get this odd issue: call comes in with Caller ID. Answer the call, you immediately get a 2nd call, no caller ID, and it's a dial tone when you grab the call). If you call 3329, this behavior does not happen (phone calls received and complete normally, no 2nd phantom call). 3329 comes in on the PRI.

Any ideas?

[Marwan ALshawi]

why u dont do this numbering translation on ur gateway for example if u use h323 ?!

[newmarket25]

We don't use H323 on this 2801.

I think we left one POTS on the 2801 for SRST functionality (which obviously wouldn't do us any good at this point, since we have the phone company disabling 3334 and forwarding all calls to the PRI at 3329).

In CCM, 3329 translates to 4074 which is an internal extension.

It's just so weird that we get that 2nd call, and it's just a dial tone. With every call! But only if you call 3334 (the line the phone co is forwarding). If you call 3329 (the line the phone co is fwding to) you don't get the 2nd call....

[Rob Huffman · Accepted solution]

Hi Doug,

I don't see this as any type of config issue related to your build. I have to think that this has something to do with the way the Telco is applying this workaround. Have you engaged them with this concern? Have you disconnected all the connections related to 3334?

Just a thought,

Rob

[newmarket25]

Yup, got the phone company involved.

But here's what makes me think it MIGHT be my build: you don't get the 2nd phantom call until you answer the first one. If you got 2 calls at the same time, I would put it to the phone company. The fact that the 2nd call is not generated until I answer the first one, sort of points to my PBX, IMHO.

[slongewa]

What do the dial-peers look like? What does the PRI show as the called number when the various numbers are dialed? I'm wondering if there's something with the dial-peers and the called number from the Telco that is causing a dial-peer to fire another call to that line at the point of connection.

Thanks,

Steve

[newmarket25]

Well you people are too fast! lol!

I just did another test, and the 2nd call is generated whether or not we answer the first one.

Would it be anything in Unity or CCM that would be doing this?? not sure were to look for dial-peers, only the telco is forwarding calls.

[newmarket25]

You were right. Unplug 3334 from the 2801, no more phantom calls. Don't understand it, since the telco is supposed to capture any calls for that and fwd to the PRI, but whatever! It's working like it's supposed to now!

Thank you!

[Rob Huffman]

Hey Doug,

Good stuff! My thinking here is that the Telco applied a "Remote Call Forward" on 3334. When this is done, generally, when a call is placed to 3334 there is one ring cycle still generated before the actual forwarding takes place. This would probably be enough to trip the FXO as an Incoming call and then of course drop off (thus the dial tone)when the call is answered.

Glad you got it fixed :)

Rob