Polycom VVX Ringback Call Waiting Tone

[cparker_RCT]

I'd like to revive this post https://www.3cx.com/community/threads/polycom-vvx-call-waiting-ringback-5-6-0.59495/
Instead of getting a standard ringback I am getting a double call waiting tone. This happens with internal and external calls, and it doesn't always do it but happens more often than not.

v16.0.910 with the sanctioned Polycom 5.6.0 firmware from 3CX.

Edit: it seems that it does this behavior internally more than external. I would imagine that once the trunk indicates call progress, it sends its own audio instead of the simulated tones in the phone.

 

[leejor]

This happens with internal and external calls, and it doesn't always do it but happens more often than not.

It sounds, (no pun intended) as if the tone-set, for the phone, is not set for the correct country. What you consider a call waiting tone, may be considered a ring back tone, in another country.
However, this should not be an intermittent problem, it is either wrong, or not. Just concentrating on internal calls, for the time being, is it consistent, with the double tone?

 

[cparker_RCT]

It's occurring 99% of the time with getting the wrong ring-back being played on the VVX's on internal calls. If I make an external call, I hear the start of the incorrect ring-back tone then immediately hear the correct version playing.
Yealink phones don't seem to be hit with this on the same installation.