Voice quality problem? SOMETIMES only`?

[Thona]

But not time dependant.

I have 3cx current version running on Hyper-V. VERY low load. Voice quality varies greatly - sometimes it is horrific bad, most of the time quite good. Well, very good - it is a phone system, not a hifi setup.

I seem to nail down the bad quality to people using VOIP on the other end, too (through a pbx) and / or mobile phones - but then also not in all cases. In these cases sound is seriously distorted - bad enough to make the call pretty unusable and I fall back to my mobile phone.

Anyone an idea where to look next? I do not think this is a 3cx problem per se, but could also be something alone the line of my voip provider, or general interoperability. But any tips would be welcome. I do not think this is a performance issue on my side etc., because at the same time other calls work perfectly in parallel, and we can repro it (i.e. call alternatting numbers, it is always the same number with problems).

 

[h2009]

Can you give some information on:

1) what provider you are using
2) free or paid version?
3) Have you got QoS setup?
4) Do have the issue if you configure a phone directly to the sip provider
5) have you run a line quality test - i.e. http://myvoipspeed.visualware.com/

 

[leejor]

I have experienced the same thing when calling people that I know are using VoIP at their end. There are so many variables that you have no control over once the call leaves your modem. Unfortunately any noticeable voice problems just add up. What might be acceptable when calling from an analogue line into a VoIP phone, becomes annoying when calling that same line from another VoIP phone because of how the call routes. Many companies that offer VoIP service AND are also the ISP can control the quality of the call up to a certain point on their network by giving the voice packets priority. Companies such as Vonage have no control of the network that you use their service on, and quality can suffer if there is network congestion anywhere between two callers.

You can have the fastest fibre connection between your PBX (3CX) and your ISP, but unless the call is staying with the same ISP all the way to the other end, it will be difficult to correct noise/echo problems, outside of your control, which are really just lost or delayed packets.