Remote Rig

RRC 1258 Support in English => General discussion forum => Topic started by: K3TN on 2016-11-02, 12:19:06

Title: Audio Dropouts on an Internet Connection that works fine with Skype
Post by: K3TN on 2016-11-02, 12:19:06
The W4AAW remote operation has a remote K3/RRC position and two other remote positions that use Skype and VNC to remotely control PCs and FT2000s. The Internet connection is a broadband wireless service that is specified at 8Mbs down/2Mbs up.

We are having severe audio dropouts on the K3/RRC position while the other two positions Skype audio continues uninterrupted. We are also seeing frequent "Radio Reset" events with N1MM+ networking on the K3/RRC position, where N1MM says it has lost contact with the radio - does not happen on the other two positions that are running N1MM+ on PCs on the radio-side LAN.

The problem definitely seems Internet traffic related - if only the K3/RRC position is active *and* there is no local (non-shack) Internet use, the audio is fine. During a contest when the two positions running Skype (and N1MM network traffic) we start to see both the audio dropouts and increased N1MM radio resets. In that case, total network traffic as seen by the Internet router is generally under 100 Mbs.  Outside of a contest, if the non-shack use goes up above that level, we start to see the problem even when only the K3/RRC is active.

We are running RRC audio at the lowest bit rate. I've increased the jitter buffer/delay settings from the default of 4/3 to 8/6 and 12/8 without seeing improvement. I still have the packet size set at 20. That will be the next thing I will try.

Running a 100 ping test, the average latency is always below 25 ms but the max will usually show up as 250ms or as high as 500ms, but even longer ping tests come back with 0 percent packet loss.

Question:  What are typical jitter buffer/delay and packet size settings for dealing with this kind of scenario? Is increasing above 12/8, or increasing the packet size, likely to have any real impact? Or any other suggestions for how to solve audio and N1MM+ connectivity dropouts?

Thanks and 73, John K3TN
Title: Re: Audio Dropouts on an Internet Connection that works fine with Skype
Post by: K0NM on 2017-01-22, 16:34:54
John,
I have a K3 and RRC at my ranch. I use the Verizon wireless router for my Internet connection. Every once in a while, the cell tower gets hit by lightning and the data rates drop. The ping time will change from about 69 msec to 200 msec instead of the solid 69 msec. The received audio at my Control site becomes interrupted as you describe. I run Speedtest from Ookla to look at ping time. I look at the  download and upload speeds. The data is plotted for about 10 seconds on my phone, so you can see actual data drop outs, mostly in the upload speeds. I find the Speedtest program extremely useful in diagnosing Internet connection problems, before I go searching for issues with the RRC box.
Nizar K0NM