Jump to content

Recommended Posts

Hi,

 

is it possible to measure the quality of the MoH sound? We're experiencing that the MoH sound is accompanied by a very disturbing noise when played by the PBX, if you open the file (default SnomOne moh.wav) with Windows Media Player for example everything is fine.

 

CPU or media load can't be the reason, the CPU is bored at 5%.

 

Could it be some kind of codec issue?

Link to post
Share on other sites

Is that a file that came with the audio files for the PBX or did you create it on your own? The PBX understands only a narrow subset of the WAV file capabilities, for example it will not take stereo files and the sampling frequency must be 8 kHz.

Link to post
Share on other sites
  • 3 weeks later...

Between mars and earth? Usually when the sound does not sound like packet loss, it is a problem with excessive transcoding. Remember from information theory, transcoding can only reduce the audio quality, even when transcoding "to" a great codec. If you do that a couple of times, it really sounds like smoke signs on a mointain. Least common denominator!

Link to post
Share on other sites

Maybe, if necessary ;) Transcoding might be a reason, but it also sounds like this when having MoH internally. Although I must admit that it's much more worse when you're calling from/to external, no matter if it's landline or mobile. Will do some tests on this...

 

As a question, we're using Asterisk as internal SIP registrar for Sangoma cards which are connected to T1s, the trunk PBX <-> Asterisk should be G711, but in case the outgoing line operates in a lower codec, will the Asterisk handle the transcoding or the SnomOne itself?

Link to post
Share on other sites
  • 1 year later...

I am having the same issue. I have been able to narrow it down to be that the call has to be with a cell phone. I do not think that packet loss is an issue(MOS on cal is 4.7). We are using g.729 as our default codec and g.711 as the second choice. Can you suggest the .wav format to use to try and correct this.

Link to post
Share on other sites
Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...