question

I use VVX 500 phone. When I try to pick up a headset to answer a transferred call (from my receptionist) the transferred call is put on hold and a new line is picked up. This happens only sometimes. I noticed that if instead of picking up the headset I answer using the touchscreen (which activates speakerphone) it works fine - I then can pick up the headset. Other times when I pick up the phone I get connected directly to the caller without my receptionist being able to announce the caller first. This only happens sometimes so I know that my receptionist is doing the transfer correctly. Other times if I pick up using the speakerphone button the other party cannot hear me (as if I was on mute). I have to pick up the headset for the other party to hear me. Is this a firmware related issue? If so when is the firmware update expected for the VVX 500? Thanks in advance.