I'm trying to figure out how to transfer a call with cisco SPA504g phones. I have used the default 3cx template to provision the phones. When I am on a call I see an XFER button so when I push that the call goes on hold then says enter a number. I proceed to enter an extension and hit dial. The extension rings and we can talk to each other, but there is no transfer, the original call is still on hold with the extension that answered the call. So far the only successful transfer I have been able to make is if I answer the call with 3cx phone and push the transfer button. That works just fine (I assume the 3cx soft phone does a blind transfer) the 3cx client I was using was on a remote computer not in the office and I had no sound.