# Coupled but Late: Turn-Taking Between Full-Duplex Speech Models in Unscripted Dialogue

arXiv: https://arxiv.org/abs/2610.08683 · HTML: https://mlsanity.com/paper/2610.08683/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 8 of its 25 references that are in the map.
- First posted on arXiv 6 Oct 2026.

## Builds on (most cited first, 8 of 8)

- [Moshi: a speech-text foundation model for real-time dialogue](https://mlsanity.com/paper/2410.00037/) (2024)
- [PersonaPlex: Voice and Role Control for Full Duplex Conversational Speech Models](https://mlsanity.com/paper/2602.06053/) (2026)
- [Multi-Faceted Interactivity Alignment in Full-Duplex Speech Models](https://mlsanity.com/paper/2606.11167/) (2026)
- [Instruct-FD: Can Your Full-Duplex Speech System Follow Turn-Taking Instructions?](https://mlsanity.com/paper/2607.20460/) (2026)
- [Overcoming State Inertia in Full-Duplex Spoken Language Models via Activation Steering](https://mlsanity.com/paper/2606.11386/) (2026)
- [Synchronization and Turn-Taking in Full-Duplex Speech Dialogue Models](https://mlsanity.com/paper/2605.20356/) (2026)
- [DuplexGen: Adaptive Synthesis of Human-AI Turn-Taking Dialogues](https://mlsanity.com/paper/2607.26178/) (2026)
- [Agentic-DuplexGen: Decoupling Content, Timing, and Acoustics for Synthetic Dialogue Speech](https://mlsanity.com/paper/2608.16053/) (2026)

## Abstract (arXiv)

Full-duplex speech models are trained to converse with a person, but they are increasingly made to converse with each other, in self-play data generation, agent societies, and model-based evaluation. In that loop no human absorbs a timing error: each model's turn-taking is the other's input. We ask what timing the loop settles into. Two PersonaPlex-7B instances exchange audio tokens on a shared clock in unscripted conversation, and one floor-transfer rule is applied to them and to Switchboard. Their timing is coupled: re-pairing speakers across conversations destroys it. But the floor changes hands late, at a median of 400-560 ms against 137 ms for humans, and the last 120 ms of the partner's turn, where human projection places a tenth of its transfers, holds 1% of theirs. Delaying one direction of the channel shifts the response one-for-one and leaves the run-up to it empty, consistent with a reactive wait after the perceived end rather than the turn-end projection human timing requires.