Loss of Audio output on keypads.

[gfoden]

recently the Audio confirmation, e.g. \"Night mode\" ceased on the system. As a first step I decided to look at the logs rather than diving into the alarm box and checking the speaker wiring, which I think was the right decision.
I upgraded the configurator to 3.12.7.0 and, incidentally, it gives an \"Unhandled exception\" error whenever you click on a topic in the left hand window. (Windows 10 32 bit fairly up-to-date) It said there was a module error (I presume in comfort) and updated that and then I was able to download the log. (Pity it doesn\'t paginate so you can print off the last 50 entries or so.) 
What I spotted was that a recent entering of my unlock code to see if would clear things triggered the following sequence.
DSP/Voice fail 96. 
DSP/Voice Restore 97. 
Reset 97. 
After this audio was restored.
Where can I find this in comfort? are they action codes or responses. Where can I find a description of what is going on? Is something failing? should I take action? Why did entering the user code fix things this time but previously had not fixed things.
Any pointer to documentation or answers would be appreciated.

[slychiu]

The event log is most self explanatory. Details can be found in the Comfort serial protocol, download from https://www.cytech.biz/serial_interface_protocol.html under the command E?
DSP Voice failure means the voice had a problem. If the voltage to the Comfort drops suddenly, the DSP voice engine may shut down ato protect itself against corruption. A reset normally restores the function unless it is really corrupted
So in your case it restored otself after the reset which is fortunate