Stumped on Audio Drops

[Radioboy50]

I have a TS-480 utilizing a high speed internet connection. Test's at over 12M up and download.
At random times the audio drops and the red led on the mic connectors comes on. This lasts for about 2 seconds and seems random.

I have adjusted the RX Jitter to 10 and the RX Delay to 9 with Pkt size of 20 on both Remote Rig units. No change ---

The routers on each end of the set-up are Apple Time Capsule. I have configured both routers so that the Remote Rig unit at each end is in the DMZ so no port forwarding etc. All the units have the latest software updates.

Anyone have an idea what could be creating this problem???

[sm2o]

If the RED LED comes on you have already lost the incomming RTP stream for a few seconds. This is nothing which can be fixed by the RRC.s or it's settings. This is a problem for the ISP. If you connect from a different place you can find out if the problem is in the control or radio end.

73 de mike

[Radioboy50]

Thanks Mike,

Do you have any theory as to way the ISP would drop the stream? Could it be something in the Apple router??

[HB9AZT]

Had same issue at a customer's installation. Problem solved by changing port 5060 to another port, was used by router for telephone connections. Even when there was no phone connected to the router, audio dropouts appeared due to port collisions.

73 de Mark, HB9AZT

[Radioboy50]

Now I noticed that I can make the audio drops occur if I change the frequency dial on the TS-480 the dial will lock up and the audio drops, red led comes on. This lasts for about 3 seconds the goes back to normal.

Both ends of the RR are in the DMZ of the router - I wonder if I should change the command port?

[sm2o]

If turning the VFO cause audio drops you have to narrow bandwidth. Change to audio quality 0 and try. You can check in the manual how much bandwidth is needed for the different audio qualitys. Remember that DSL connection are not symetric, the uplink can be quite narrow.

73 de mike

[g4swx]

It is also highly likely that the drop outs could be caused by bursty Internet traffic to/from either end of your link.

Typical causes of this are webcams, particulary at the radio end, Outlook like mail clients at either end and IPTV applications at the control end. You must limit the upstream bandwidth of all clients at the radio end, except possibly the remote rig itself. In particular I would recommend setting an upsream limit of 100Kbps (unless you have >1Mbps upstream bandwidth) on all other clients on that network. On the control end if you have ~10Mbps then set the limits at around 1Mbps. Note this will 'slow' access to the Internet for other usage and may well stop most IPTV applications from working.

Sometimes you will find particular routers, particularly the cheaper ones(even Apple!) are part of the problem. If all else fails try changing the upstream and then the downstream router.

Rx jitter/delay settings of 10 are often not enough, I have to run with 16/15 AND I had to reduce the audio quality setting to 1 to maintain a basic link between two different ISPs.

Even with an all private network it is not easy to elimate all such drop out except by the introduction of rigourous QoS limiting the bandwidth that can be eaten up by other systems on the network. HTTP traffic can be a real pain and should be constrained!

Sometimes I can also cause such a drop-out by sending an HTTP request to the web server on remote rig (radio) box!

Fixing drop outs just comes down to paying very close attention to what is running on your IP networking(assuming the ISP connection is OK). I would also recommend using pingtest.net for testing your ISP/router.

73
John G4SWX