Running FreePBX distro, 6.12.65 as a virtual machine.
I’m having a heck of a time with the audio on this machine. Around the beginning of the year or so (can’t pin it down due to lack of activity around the holidays), we started getting some serious ‘chop’ in our audio, especially in conferences (though it is present in every call, it’s almost impossible to use a conference room due to the amount of audio chop).
I investigated our UDP traffic, and had our network guys do extensive testing on the network and internet connection to make sure we weren’t just dropping packets due to a bad piece of network hardware. Finally did a dahdi_test, and found this:
Opened pseudo dahdi interface, measuring accuracy... 99.997% 99.913% 99.809% 99.997% 99.945% 99.750% 99.809% 99.907% 99.901% 99.939% 99.927% 99.907% 99.900% 99.858% 97.374% 99.947% 99.995% 99.903% 99.656% 99.546% 99.995% 99.998% ^C --- Results after 22 passes --- Best: 99.998% -- Worst: 97.374% -- Average: 99.771525% Cummulative Accuracy (not per pass): 99.867
Pretty bad. I installed a brand new VM with similar settings and a fresh copy of freepbx, latest version. Same thing. I put it on a different host within our organization, same thing. If I go to another, similar host at a different company, they have a perfect dahdi_test.
So it’s probably something in our VM configuration, I concluded. Me and our ESX guy tried increasing the priority given to the VM by setting the 'Latency Sensitivity" to “High” and reserving 2 full cores and 3gb memory, dedicated them to the PBX. It made absolutely no difference; in fact, I got worse results occasionally.
So we decided to get a Sangoma USB VoiceTime device; plugged it in and attached to the VM. I had to download and compile an older version of Dahdi (2.5 or so) in order to get the voicetime drivers to compile and install/work. I had to contact support to make sure the device was installed and working. They verified that it was.
Installing the VoiceTime device helped a little bit, but the same symptoms are still there and I have no idea what to try next. Help!
Oh, also, I lied; the dahdi_test results above were done about 10 minutes ago with the voicetime device attached. Unattached, it’s pretty similar, but actually worse.