Our VOIP provider is Vonage. We use Jitsi as our softphone (SIP) to make
call-transfers both client-side & server-side.
For the most part, the attended transfer feature works well, but, on
occasion, the transfer is dropped. I will explain in detail:
- We are able to establish 2 active lines; Jitsi has always been able to
to do this.
- We noticed the attended transfer doesn't work unless both lines are
active and not in a holding status.
- There is a 100% drop-rate when we attempt to perform an attended
transfer when the line transferring is on hold. Jitsi automatically puts
the transferring line on hold and we have to take the line off hold to
perform the attended transfer.
- However, there are times when we perform the attended transfer that
the active lines are either dropped when transferring, established but then
dropped, or one line is dropped and the other one remains active.
Again, there are times where the attended transfer works well, but there
are times when it doesn't work.
P.S. I would also note that sometimes, when the attended transfers work,
the line quality is not good --a crackling in the line.
Thank you for you time, in advance.
To Your Success,