Suddenly getting Jitter

[Jonners59]

I am running Ubuntu 10.10 within which I have a VirtualBox, on which I am running Windows7 Home Prem. Within the Home Prem I am running a 3CX IP PBX and bar an SMTP server so it can send voice mails via eMail, that is all. I have had this settup bar I used Vista Home Prem before, for about 2 or 3 years without any serious issues until the other day - when everything seemed to fall apart - but since then I am getting jitter on all calls. It is so bad it is totally inaudible.

I have set up my router/LAN switch, a Draytek 2820 to use QoS as per settings on the 3CX Blog, but it makes no difference. Any ideas anyone?

 

[Georgek111]

I have experienced call quality issues also even though i have the QoS setup. This problem only started a few days ago when i upgraded the Draytek 2820 firmware to 3.3.5.1.

This firmware seems to have a problem with classification of traffic from the PBX machine. A work around according to Draytek was to create an additional rule. This worked for me but may not be ideal for others!

Open the Class 1 Rule you created when following the 3CX instructions. Add a new class to the rule:
Rule setting:
-Local address of PBX
-Remote address: ANY
-DiffServ CodePoint: ANY
-Service Type: ANY

This will class all the traffic from the PBX as Voip traffic, not ideal but a work arround for now.

Hope this helped!

 

[Jonners59]

GeorgeK111
Many thanks for this. I shall give it a bash, though I now think mine is not actually jitter. After some time playing I think it is to do wiith processing. I think the settings within Windows 7 may be the issue or the VM... though it worked fine until I tried to install the SMTP server - now removed.

 

[SY]

GeorgeK111
Many thanks for this. I shall give it a bash, though I now think mine is not actually jitter. After some time playing I think it is to do wiith processing. I think the settings within Windows 7 may be the issue or the VM... though it worked fine until I tried to install the SMTP server - now removed.

Wireshark capture can help to understand the problem.
Sorry for the inconvenience, but there are no other ways to get objective information

Thanks

 

[Jonners59]

Thanks Stephen
A suggestion for the development.... Could it (3CX) include an SMTP capability, then it would be self contained and self sufficient?

What I need is someone who knows VM and W7 who can check things over and advise. I'm just not techie enough. :cry:

 

[Jonners59]

OK, I hope I have fixed it.

I completely rebuilt the PC/Server it is working on to ensure I flushed out everything. Fortunately that is quick and easy on Linux. Then I reinstalled the VMWare, the new virtual hard drive and a new install of W7... This time I only gave W7 just above bare minimum RAM (600Mg). It seems to have done the trick.

I shall keep an eye on it

Now I need to sort out the SMTP issue to get my voice mails eMailed to me.