I've noticed that if I create an assessment in the style of an AP interpersonal conversation, I have to trust that students are following the written instructions and not pre-listening to my recorded track (with gaps for their speaking) prior to hitting record on their response track.
On the AP or Seal of Biliteracy test students have a single track that plays with the instructions, prompts and questions and they record their responses in the gaps. Even if I put a time limitation on the assessment, technically the student can hear my pre-recorded assessment with gaps prior to hitting their record button on the student portal.
I'm not sure I've properly explaining this, please see attachment for reference.
So that the assessment is truly spontaneous we have to remove any possibility that students can pre-listen, thus is has to be a single track that when students hit "record" will play the instructions and simulated conversation and allow for recording in the gaps.