atcomsystems.ca/forum Forums TDM Business Telephone Systems Toshiba Telephones & Systems Remote IP phone users sound "under water"

Weird, ping to our default gateway is 21ms average.

Since you are basically going over the internet, Diffserv won't make a difference of call quality over the internet but can cause issues if it is turned on and the Cable companies are not configured to look for it. Diffserv would play a big role if you had an AVPN or MPLS network topology with multiple sites. It would give priority to the voice packets.

cable modem attached to phone system or at remote ip phone sites? Does cable include verizon fios, dsl type service?

I don't know how useful this will be but here at my facility we're using G711 codecs primary and G729A secondary for for phones right here on the campuses, and for remote users I have G729A as the primary and no secondary selected. I've had good luck with this setup. You'll want to use voice packet table 2 with G729A. G711 would probably be a bit too heavy for a remote phone over a DSL or Cable connection in most cases.

The setup at the office is typically how I have set it up. The IP card needs a public IP address to work, but since it is outside the router it makes it difficult to have a router proritize traffic.

Ping of 81ms from end to end is pretty good, if it is like that all the time. Last time I was trying to troubleshoot call quality, I had very good ping results most of the time, then there would be spikes of like 500+ms. I was trobubleshooting on the IP phone side, but the delays were on the phone system side.I believe it was some server that would burst a large amount of data periodically, and that is when the calls sounded bad.

You can definately try using G729A to see if it works better. If delay is a problem and not bandwith, then it could sound worse.

In the office now and have IP phone with me. IP phone is connected to office network, phone system is on own cable modem separate from network.

ping from work station connected to ip phone was 58 ms average, but at other ping attempts, there were timeouts and loss 25%. I spoke with someone on the ip phone for a while. Every so often, I could not hear them and then call got disconnected eventually. Good quality most of the call. Call was to another digital extension in my office.

Diffserv is still enabled. My toshiba guy did not want to disable it.

The cable modem dedicated to the phone system is 5 down 800K up. Is that enough, or do i need to bump it to 10 down, 2 up?

You can have him at least try it and if it doesn't get better or fix it you can always turn it back on.

Thaks for the reply. I think I can do it in eManager. Is it in IP-Telephony-->system IP data assignment-->03 Diffserv disable?

Are there any other settings I can and should tinker with? Audio codec for remote IP phones are G711 with secondary audio codec for full IP station at G729A. Any others?

Using cable modem at one remote IP phone and verizon fios at another and cable modem at the system with 5 down 800K up.