Double Tones on Conference Lines

[stevech]

I used to have a Linksys PAP2 ATA used with ViaTalk (Asterisk), not VoIPo. It garbled touch-tones received badly. I could call another landline and push DTMFs - they were badly clipped and distorted. As a result, most but not all IVRs (voice mails, conference bridges, bank logins, pharmacy prescription refills) failed. Not the analog phone's problem- tried many. All work OK on a POTS line. Tried changing to SIP signaling from the ATA but that didn't work because of VoIP service provider SS7 bugs.

None so far with this VoIPo ATA from Grandstream.

[MarkTomlinson]

Well, a week later and the problem persists. I guess I get to open up a ticket.

But here's the weirdest part; I decided I'd record it happening so that I had something to show Tech Support. But every time I entered *28 and the phone number, it worked! Twelve times at two different times of day, if I dialed *28877xxxxxxx and then the conference code it worked every time. I alternated that with just dialing 877xxxxxxx and the conference code to ensure I was still having the problem.

So why is it that dialing the number directly creates questionable tones that the conference line sporadically interprets as double tones, but dialing with *28 in front does not?

I guess I'll open a ticket and find out.

[stevech]

Maybe due to routing that any given call takes, even to the same number?

[MarkTomlinson]

Maybe due to routing that any given call takes, even to the same number?

Something like that, I think. Try dialing *28 and then wait a moment. I get a second dial tone with higher pitch. This leads me to believe the call is going through a second ATA (or something to that effect) which interprets the tones correctly from my ATA and then passes on higher quality tones.

Because of the above, and since I seem to be the only one having this problem, I believe it is the Linksys RT31P2.

I've opened a ticket and will let everyone know how it turns out. That way if anyone else experiences something similar, they can point Tech Support here.

[tritch]

The call routing is different for *28 calls as stated in vPanel:

Note: This feature is intended for occasional use only. When you record a call, the audio for the call is routed through our Call Recording server instead of our primary media gateways and as a result call quality may be reduced.

[MarkTomlinson]

The call routing is different for *28 calls as stated in vPanel:

Note: This feature is intended for occasional use only. When you record a call, the audio for the call is routed through our Call Recording server instead of our primary media gateways and as a result call quality may be reduced.

Yep. That was it. Got the following reply to my ticket;
"Please try to call into the conference again. I've updated your DTMF method and have moved you to a closer server."

Problem is gone! As an added bonus, I was perfectly fine with my call quality but now it's even better. Talked to my boss for about half an hour and kept thinking, "Man, this is clear".