T53 SIP Issues

[jskinner97]

Hi all,

Keep having the same issue at one of our sites. Only affecting Yealink T53s, issue is resolved after a reboot of the device. Bascially every now and then the phones deregister from the PBX, and show "No Service". NAT rules are in place, and I can see them de-registering on the correct ports, and upon reboot registering on the correct ports.

Have run a PCAP whilst the phones are down, and attached a screenshot of the PCAP with the phones doing REGISTER and OK messages - not sure if this helps or not.

I have replaced the router on site, factory reset the phone, used default templates and the issue still occurs.

We do have another site, same PBX (same customer) who uses T58s and they have no issues - same router too.

I am thinking of installing an SBC, but unsure if this would resolve the issue. Please could someone help?

 

[YiannisH_3CX]

Hello @jskinner97

Your screenshot shows that the phones are registering correctly (assuming your PBX SIP port is 5186) and they get a reply from the PBX.
But it you are having problems then the 3CX SBC is the best solution. The phones will contact the SBC locally and the SBC will be the only device contacting the PBX so i would recommend going down that route.