[VoiceOps] Alarm panels and how they dial DTMF digits - pots migration from DMS to Metaswitch issue

[Brandon Martin]

On 2/13/23 17:46, Nathan Anderson via VoiceOps wrote:
> You wrote this here, but elsewhere what you wrote seems to suggest the symptoms seem more "random" than this (sometimes all digits are correctly decoded and passed on, sometimes different digits or different numbers of digits are missing, etc.).
> 
> If the mode of failure really is as consistent as you suggest here, though (or even if it happens the majority of time), have you considered recording the audio coming out of one of the fire alarm panels while it's trying to dial, so that you can take a spare Adtran, put it on the bench, configure it identically to one that you have in the field, and feed it a recording of the fire alarm panel dialing out, in order to reproduce the issue?  If you can repro outside of production, then you can test & iterate much more quickly (as well as at your own convenience) than when you are forced to test on an actual customer installation.

I'll second this and add that not only would this give you an 
opportunity to bench test things, but it would also let you easily rule 
out certain settings like impedance and levels since you can quickly 
vary them on both ends.  Just seeing if it does or does not reproduce 
reliably based on playback in both the original and lab environment 
would be useful.

Another thing nobody's mentioned is trying to get one of these fire 
panels for yourself.  If they're as old as you're implying, they may 
well be readily available cheap on the secondary market.  If you can get 
one, not only can you lab IT up, too, but you can also get your hands on 
all the various configurables it may or may not have that your customer 
is being less than cooperative with.
-- 
Brandon Martin
Mothic Technologies
317-565-1357 x7000