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2025-02-04 04:38 PM
Hello,
I am trying to connect a building alarm panel dialer to an AudioCodes 1288. No matter the settings I change the modem lines don't seem to synch up. I monitor the line connected to the legacy PBX and the communication seems the same. I know there is some delay which is probably causing the issue. I see modem settings in the Audio Codes, but the recommended Fax settings from Zoom seem to be interfering with them.
Has anyone had any luck when attempting this before. I have also tried with a Grandstream ATA with no luck.
Thanks,
Derek
2025-02-05 08:57 AM
Who's the alarm company?
2025-02-05 10:04 AM
I am trying to work with older Bay Alarm panels.
2025-03-05 09:00 AM
I have the same problem with Bay Alarm panels with Grandstream and Audiocodes. Any information would be appreciated. We are trying to avoid replacing several panels.
2025-03-05 09:53 AM
If this is strictly a dialing issue? I suggest you download a program called syslog viewer from the Audiocodes website. In your Audiocodes MP1288 syslog settings, point the address to your local desktop/laptop running that application. Then try initiating a call from the panel to Zoom to see what the SIP traffic is doing with the call. In our setup with our local alarm company, we don't use any fax/modem settings on the audiocodes gateway. However, not all alarm companies are willing to make things work with a VOIP provider. When your converting SIP to analog signaling, that transcoding causes early disconnect.
2025-03-06 07:30 PM
Hello @dstokes805 Modems and Faxes over IP are always tricky, especially if you are dealing with older equipment that don't support the newer standards. I don't see any information about the Alarm system but I would suggest first of all to contact them as ask them what is the recommended and what is the maximum speed their modems support because I was reading both, Zoom and AudioCodes documentation and it seems that is one of the things you need to configure. With that information you can try to match what they are asking and prevent the AudioCode trying to negotiation something that is supported by Zoom but not the Alarm system.
Now, from the AudoCode documentation, this are the options you need to try (if you haven't yet), in the same order I put them here:
I know it is a lot but good luck; I hope one of this options works for you, and let us know so other people can benefits from your "pain" and save them from "suffering".
Vinnie.
2025-03-27 08:56 AM
We have found the solution that works for our fire alarm panels. Give this a try and let me know how it goes. We also built an Alarm Profile (Tel Profiles) listed below
On the Gateway we built a Profile with the following specs. You'll need to change the DTMF Transport to 2 in http://MP-1288_IP/AdminPage.
Parameter Name: DTMFTransportType Enter Value: 2
DTMFTransportType = 2
CallerIDTransportType = 3
FaxTransportMode = 3
V21ModemTransportType = 3
V22ModemTransportType = 3
V23ModemTransportType = 3
V32ModemTransportType = 3
V34ModemTransportType = 3
FaxRelayMaxRate = 3
FaxRelayECMEnable = 0
FaxRelayRedundancyDepth = 2
FaxRelayEnhancedRedundancyDepth = 2
FaxModemBypassCoderType = 1
RFC2833TxPayloadType = 101
ENABLEMEDIASECURITY = 1
PLThresholdLevelsPerMille_0 = 5
PLThresholdLevelsPerMille_1 = 10
PLThresholdLevelsPerMille_2 = 20
PLThresholdLevelsPerMille_3 = 50
CallProgressTonesFilename = 'AudioCodes_call_progress_usa_tones_13.dat
Profile settings
Name Alarm
SIGNALING
Profile Preference 1
Fax Signaling Method No Fax
Enable Digit Delivery Disable
Dial Plan Index -1
Call Priority Mode Disable
BEHAVIOR
Disconnect Call on Detection of Busy Tone Enable
Time For Reorder Tone [sec] 255
Enable Voice Mail Delay Enable
Swap Tel To IP Phone Numbers Disable
IP-to-Tel Cut-Through Call Mode Disable
DTMF Volume (-31 to 0 dB) -11
Input Gain (-32 to 31 dB) 0
Voice Volume (-32 to 31 dB) 0
Enable AGC Disable
Enable Polarity Reversal Disable
Enable Current Disconnect Enable
DID Wink Disable
Enable 911 PSAP Disable
Coders Group AudioCodersGroup_0 View
RTP IP DiffServ 46
Signaling DiffServ 24
Enable Early Media Disable
Progress Indicator to IP
ECHO CANCELER
Echo Canceler Line Echo Canceller
EC NLP Mode Adaptive NLP
JITTER BUFFER
Dynamic Jitter Buffer Minimum Delay [msec] 10
Dynamic Jitter Buffer Maximum Delay [msec] 300
Dynamic Jitter Buffer Optimization Factor 10
ANALOG MWI
MWI Analog Lamp Disable
MWI Display Disable
MWI Notification Timeout [sec] 0
ANALOG FXO
Two Stage Dial Yes
FXO Double Answer Disable
FXO Ring Timeout [100 msec] 0
Flash Hook Period 700
FXO Consultative Call Transfer Disabl
2025-03-27 09:15 AM
Thank you for sharing these settings. I will give them a try today.
2025-03-31 07:54 AM
Did this resolve your issue.
Thanks,
Anthony
2025-03-31 08:46 AM
It did not, but I am going to attempt again tomorrow to double-check that I had all of the settings correct.
2025-03-27 10:10 AM
So it had nothing to do the the the CODEC but with the DTMF Signaling
DTMFTransportType = 2 is equivalent to Out-of-band DTMF using RTP payload (RFC 2833).
Nice finding. I wonder if the rest of the people having similar issues can test and relay their results.
2025-10-24 02:41 PM
I have a similar but different issue. We have a lot of Audio Codes MP1288's registered to Zoom . As we migrate them to Zoom and running across different issues as we migrate various devices connected to them. We recently started migrating older HoneyWell Vista-128BPT alarm panels. We couldn't get them to work until we changed the setting Declare RFC 2833 in SDP set to No, otherwise is it a default config. However as this is a system setting it resulted in 2 issues> 1 Analog ATA callers to voicemail unable to send DTMF and prevented them from logging into the voicemail system on Zoom. 2 Elevator phones are no longer able to be programmed via DTMF.
My interpretation is that some ports/device need inband dtmf while others do not. We use Zooms recommend settings for the fax ports which works well. I'd like to change the Declare RFC 2833 in SDP set to Yes as it would work voicemail and phone tree users. Then set the alarm pannel ports to Declare RFC 2833 in SDP set to NO or equivalent allowing them to work as well too.
My bench depth on these various setting is on the week side. Maybe your bench depth would point me in one of the directions above to start with. Any suggestions?
2025-10-27 02:08 PM
We have seen a similar situation on our MP-1288s. As we have multiple MP-1288s I have designated one to Declare RFC 2833 in SDP set to NO. I know most of our devices don't go here, except the Bluelight phones we have that require this setting. There is a way to designate the DTMF option with the IP Profile, but the Declare RFC2833 in SDP is a global setting. At least, I have yet to find a way to alter it by port.
2025-12-08 07:01 AM
dstokes805,
Wondering if you have inquired with AudioCodes for a solution?
I askes Zoom who directed me to AudioCodes. AudioCodes told me I needed a support contract to work with them, which we are working on. Maybe you have a support contract with AudioCodes. They should be able to tell you if they have a solution.
- Monte
2025-12-10 10:20 AM
Hello Monte,
I reached out to AudioCodes a few years ago when I first was having this issue. They stated that this should be able to work, but were pretty bad about following up on this. We had some professional services hours allocated for this, but the issue was never resolved.
2025-12-10 11:48 AM
Thanks for the info. I am trying various settings to see if I can make it work and will reply with success. We also have the same ATA's on Clearspan that do not have this issue. I am trying to reverse engineer that too. It may come down to some feature Clearspan has that Zoom does not. I suspect not, but IDK.
Maybe some version of the Zoom fax modem settings for the ATA will work.
2025-12-10 11:54 AM
Do you have TLS on the Clearspan?