Helllo: Pamela in sales told me that G.729 is available in the free edition of Zoiper 5 Desktop. See below for exact version. Although I am considering buying the PRO version, if G.729 is supposed to work in the free version but does not, I have doubts if it will work in the paid PRO version. Other formerly 'BIZ' codecs are in the list like Opus, Speex, and G.726... Only G.729 is not listed under "available" or "selected" codecs. My SIP server supports G.729, I use it with other phones. Thank you.
Phone version: Zoiper5 5.2.19 for Linux 64bit
Library revision: v2.8.99
Phone revision: 5.2.19_Linux
UI revision: 1.1.35