Keith Posted September 26, 2012 Report Share Posted September 26, 2012 Greetings, We're running Snom One on a MacMini in our small studio in Seattle. I am new to SIP Trunking and the deeper points of telephony, but have managed to get our system with 6 extensions and Auto Attendant doing all the fantastic things we needed like cell phone integration and VM as Email, etc. We are running it over our Comcast Business Class broadband connection (which typically clocks at over 30MBS down and 20MBS upstream and clean for packet loss and jitter). Broadvox is our SP trunk provider. Generally it all works great with the exception of the outbound audio which our callers say is often "choppy" with lots of small intermittent dropouts. Sometimes it's smooth as butter and other times close to untenable. No echo, no distortion -- just stuttered or choppy. Broadvox said they saw some serious RTP packet latency that could be the culprit. It seems to me that with the bandwidth we have and the rather straightforward network, that we should have no trouble sending out audio smoothly. Anyway, I've tried everything I know how to do and can't solve this problem so need someone knowledgeable to take a look I think. Does anyone have any 'AHA' ideas to solve the problem -- or possibly a reference to someone in the greater Seattle area that is good with SIP and Snom? Here's our system profile. (Oh, I also can't seem to figure out why we have "-25% Available File System Space". We've got tons of hard drive space available...) Thanks in advance! Version: 2011-4.5.0.1050 Coma Berenicids (MacOS) Created on: Apr 2 2012 12:05:17 License Status: snom ONE free License Duration: Permanent Additional license information: Extensions: 10/10 Accounts: 25/30 Upgrade: 01 01 2013 Working Directory: /Applications/snomONE/conf MAC Addresses: C42C032AEB58 C8BCC8E0CF02 DNS Servers: 192.168.0.2 68.87.69.146 68.87.85.98 CDRs: Duration(4d): trunk = 57, extension = 52, ivr = 64 Calls: Total 45/5, Active 0/0 Calls SIP packet statistics: Tx: 21195 Rx: 20699 Emails: Successful sent: 10 Unsuccessful attempts: 0 Available file system space: -25% Uptime: 2012/9/25 17:14:08 (uptime: 1 days 03:08:49) (41712 42817-0) WAV cache: 2 Number of HTTP sessions: Sessions: PAC=0, HTTP=1; Threads: SIP=3, HTTP=6 Domain Statistics: Total Domains: 1, Total Accounts: 25 Quote Link to comment Share on other sites More sharing options...
Vodia PBX Posted September 26, 2012 Report Share Posted September 26, 2012 Even with a lot of bandwidth, you might experience problems e.g. when sending large emails out. It does take some time before a MB is sent out. The good news is that upstream audio is easier to fix than downstream audio. As you control the router on from the CPE to the Internet, you may also control which packets are being out first. Many routers today have QoS filters that you can program. For example, if the PBX is on a specific IP address in the office (and there is not other service running on that system that sends out traffic to the Internet), you could just give that IP address a higher QoS priority than the other devices. The ActionTek routers that come with FiOS from Verizon for example to my surprise have this feature. But there is also a lot of other router equipment available out there that has a QoS menu. If you like, give us the IP address and credentials for logging into the router (private message, along with the IP of the PBX) and we can take a look around. No need to fly to Seattle for that ;-) Quote Link to comment Share on other sites More sharing options...
Keith Posted October 4, 2012 Author Report Share Posted October 4, 2012 Thank you so much for the reply and offer and I apologize about my late reply. We did manage to enable QoS for our PBX PC to prioritize VOIP traffic and it seems to have helped a fair bit. We now only rarely get the choppy audio and I'm guessing that's out of our control and being affected once our packets get to the WAN which we can't control (unfortunately our cable ISP, which is Comcast, can't or won't allow prioritizing one type of data over another on their connection). All we can do is make sure the VOIP packets get to the WAN first, as far as I now understand. Quote Link to comment Share on other sites More sharing options...
Vodia PBX Posted October 4, 2012 Report Share Posted October 4, 2012 Right. It is important that on the uplink you send the packets in the right order; then when they are in the hands of the service provider, they are all the same again. I have heard that when the kids come home around 3 PM in the afternoon, even the backbone starts dropping packets because of all the games going on and there is very little that you can do about it except building up your own network. Quote Link to comment Share on other sites More sharing options...
Keith Posted October 4, 2012 Author Report Share Posted October 4, 2012 I've heard similar stories as well! My hope is that we've minimized the problem to an acceptable level. Otherwise we'll have to spend the extra $$ and get a dedicated connection for our phones from a provider specializing in VOIP -- which would defeat the money-saving reason I switched to a SIP trunk. We are moving our office soon within the same building so may explore if there are competing ISP's we could switch to that can manage QoS (and maybe one that offers SIP trunking as well since then there's less finger pointing when there are problems). Quote Link to comment Share on other sites More sharing options...
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