Calls cutting in and out

We have had complaints where users cannot even understand people because the lines cut in and out. I checked the bandwidth and it is 10/2 which should be fine for 5 phones. Any idea what I can check?

first i assume your phones are remote (not on the same local network as the pbx). is your bandwidth dedicated or shared with data (pc’s, etc)? if shared you really need something like an Edgemarc session border controller that does traffic shaping. the bandwidth you mention, if dedicated is plenty for 5 phones, but if the bandwidth is shared and someone sends an email with a large attachment, or does something that bursts a large amount of data, you will find that voice cuts out.

Agreed - 10M down is decent for 5 phones/people but 2M up is trivial for any one person to saturate.

Being that the complaint is that your users are having problems hearing callers. the download leg is the one getting saturated, so even that 10M is not enough for them.

If you can get an edge device that enforces the QOS and lets the voice go first do that, but if you can’t, either get a MUCH faster circuit or get a second circuit and dedicate it to the phones.

G711 is 82Kbits/Call so for 5 users to all be on at the same tine, you would only need about a 500K DSL circuit - that should be cheap enough. Just make sure that both the upload and download speed exceed 500K - DSL is almost always sold Asynchronous - Faster down than up.

You most defiantly want to implement QOS. We use the edgerouter lite from ubiquiti on a large number of our installs. To configure the QOS it is as easy as simply turning it on. That’s it. If you can replace your current router with this one it would be a piece of cake.

Even if you cannot replace your current router you can still install this one and dedicate it to just the phones. Connect it’s wan port directly to the modem (the setup won’t work really unless your isp allows you to have a second wan IP) and then plug the LAN port into your switch. Tell your phones to use that router as the gateway instead of your currently installed router. There you go a separate network for just the phones and fully QOS capable, separate IP scheme, separate dhcp … everything you need.

This router also supports failover to a backup internet connection as well a real sweet solution for a small to medium office.

And did I forget to mention the best part, it’s only about $100

They are great little routers. Only real downside is the USB storage die after a year


Havnt had any of those problems yet but I’ll be watching out for that. Been using them for about 9 months.

@tonyclewis Just to follow up I did speak with my ubiquiti reseller rep today and posed your statement regarding failing USB. He did acknowledge that they had a problem however any sold since june 2015 should be good. I was informed that they have used a different vendor since then with little to no issue … at least not yet. Time will tell.

Another vote for fixing QoS with a Ubiquiti. I’ve been using the Unified Security Gateway router with QoS for small client offices and remote offices. Cant go wrong with $100 for a solid QoS and VPN business router. Another $100 for rock solid Wifi with the UAP-AC-LR access point

And I connected all of the client sites to a DigitalOcean VPS running Unifi Controller software (free) where all the devices can be configured and monitored centrally.

we did fix the issue. It was Sip alg on the modem

Well probably Comcast if this is the Sentinal I’m thinking of. Yup u need to make sure that modem is in a full bridge mode when you use your own router.