I don't have a sound on domain account in zoiper, when i test device in windows >sounds>play headphones workes, when i switch account to local administrator sound in audio wizard in zoiper works. i don't have idea what could it be
If there's a difference between the user accounts, microsoft has added new privacy options that block some applications by default to use the microphone and even the headset. See this(http://maxedtech.com/fix-microphone-not-working-in-windows-10-1803/) link and make sure that microphone access is enabled as shown on point #2.
thank you i found, it was mute in "volume preferences and application devices"