Voxer walkie talkie and Voiceover

Hello! I am using Voxer walkie talkie and it works fine. But I have one problem. When I shall talk to anybody I must hold the button down for talk and then release it when I am ready. Now I discovered in later version that I can lock the talk button by sliding it to right, but I can't get it to work with Voiceover. Has anybody solved this problem?