"Reject call" behaviour when multiple desk phones are connected on the same extension

[Connexium Partner]

Hello all,

We have a tiny customer using 2 Granstream GXP2130 connected to the same extension number. I just migrated them to v20 as part of our v20 beta testing. (Customer is cool with that)

When a call comes in, both phones ring. On v18, one receptionist could press "reject" to make her phone stop ringing, and the second phone would keep ringing.
Now, on v20, when she presses reject, both phones stop ringing, and the call goes to voicemail right away.

What setting could affect that or what should I check to get back the old function?

This is the shared extension's current settings:



Thank you for your suggestions

 

[Alphabetic]

I know on Yealink's there is a button for silence. Does the grandstream have one?

 

[Connexium Partner]

Nah, I could not find a way to make the phone go silent. It would have been too simple!

It must have something to do with the SIP Code the phone sends back to the PBX when pressing "reject".

Unless someone has that knowledge fresh in their memory, I'll probably have to do a capture to see the code sent by the deskphone, and then see if I can change that code either in the phone settings to something that the PBX will not interpret as send to voicemail but keep other phones ringing instead.