I am having an issue performing an attended transfer using a DP720. An attended transfer goes through and the destination extension and incoming caller are partially connected but the end result is that the audio path from the incoming caller to the destination extension is fine but the incoming caller continues to hear MOH. I have been working with my PBX vendor (Asterisk system) and they say the Grandstream 2xxx series handsets work. They say that the 2xxxx phones have “Auto-attended transfer” as a menu option but I cant see this on the DP720. Hopefully someone can provide some guideance.
Many thanks in advance