Voicemail quality issues


We have installed about 6 different Freepbx servers for various customers all running the latest release of FreePBX on Dell poweredge servers or Dell Optiplex computers, each customer having no more than 10 extensions, so small systems.

Voicemails are randomly coming in where there has got to be a transcoding issue while it is saving the .wav file. When you listen to the recording of the voicemail it recorded at about half time and sounds like the person is taking a verify long time to speak, kind of like they are drunk. The call is ulaw as I have disabled all other codecs on the trunks because I was thinking there was an issue with the G729 call saving as the wav49 wav file but it is still happening.

I also, one time so far, was able to replicate the issue and when I called in, the call was perfect quality listening to the IVR and voicemail greeting. I then left a voicemail and the wav file that was emailed to me. My test voicemail played at about half speed and I sounded like I had one too many scotch’s. It will also play like that if I go into my voicemail via my desk phone and listen to it that way.

I have the default settings setup where it is saving as wav49, I have not touched any voicemail settings.

Please help and thank you.

Do yo have cards to interface the PSTN? I´m wndering what kind of timer you are using for your system.

These are all using SIP trunks with Net2Phone.

Also, I’m using whatever default timer comes with FreePBX. I have heard some people say turn off NTPD but not sure if that would actually make a difference.

Well I was talking about the asterisk timer not the Time of the system.
Take a look on this link: https://wiki.asterisk.org/wiki/display/AST/Timing+Interfaces and check in your system what are you using with the command:


Thanks so much for responding. I do realize those are two different things, I could have worded that better.

This is the result from module show like timer:

Connected to Asterisk 11.17.1 currently running on mailwash (pid = 2651)
mailwash*CLI> module show like timer
Module Description Use Coun t
res_timing_timerfd.so Timerfd Timing Interface 1
1 modules loaded

This is the default correct? I have not made any changes to that, or at least thought I hadn’t. Thoughts?

Thank you!

I haven´t used the latest FPBX distro recently not sure if you can swith that in the advanced settings or verify in the modules directory if the dahdi timer exist just to switch and test.

I will give that a try, thank you.

Does the timer affect how transcoding is done, like from ulaw --> g729 during a call?