Yealink T46S/T40G muffled/feint audio

[Stacy63]

Hi guys,

Have rolled a brand new 3cx v15 installation(all updates installed) installed as a hosted system to one of our clients. They have 6 x T46S phones and about 20 x T40G phones (latest supported FW by 3cx) All provisoned via 3cx using Direct SIP(Stun)

The are receiving endless complaints of callers not being able to hear them clearly(They sound far away and feint) and they are complaining on there end that callers sound muffled to them

All firewall checks/tests have been done. We are using G729 codec as that is what our sip provider uses. The phones do have G722 enabled(Yealink default) along with other codecs however G729 is first priority.

I have done quite a lot of research and some people say it is a FW issue while others beleive thats just the way the phones sounds. Either way the client is not happy.

The FW they are on currently is T46s: 66.82.0.20 and the T40G: 76.82.0.20

Has anyone run in to this problem before? Or could point me in a direction to start looking?

We have rolled out any installations using T23G and have never had this problem. First time using these two yealink models. apkjunky

Thank you.