sundance-communications.com/forum Forums TDM Business Telephone Systems Toshiba Telephones & Systems IPT Call quality

I have a CIX 670 on rel 4.2. It has a bipu that I have some ipt 2010 and 2020s on. The BIPU has an external IP address and the phones are home user phones.

Until this week I had little serious trouble. But 2 phones started having problems - cutting in and out. They are on broadband (cable/dsl), and their codem is 729a. I had them verify no other devices were on the internet when they used the phone. I checked the qos and usually it shows little to no issues (0 % packet loss and maybe .4ms jitter- usually less). The calls are all 2 minutes or so - the quality is bad enough that you couldn't stay on the phone longer if you wanted to. I had one person reboot their router/modem and it didn't help.

I found an article that said to set the settings for the voice packet config to be 80ms tx and 80 jitter buffer (it was 40/40 before I think). That didn't seem to help.

I have a dsl line at our office separate from our T1 line that I use for testing and when I plug a phone in on it (via a linksys router) it works fine.

Any suggestions or thoughts?

End-user may be having bandwidth issues.

I suspected a bandwidth issue too, that's why I had them turn all oth pcs off.

Also, wouldn't it show up in the QoS stats? Or could thhe QoS be ok and they're just not tx/rx-ing enough?