This read-write yes/no setting enables fallback to 6 Kbps with triple buffering, the most delay-tolerant variant among the three 6 Kbps buffering options. It is reserved for links so jitter-prone that even double buffering at 6 Kbps isn't sufficient to keep calls stable. For example, an administrator troubleshooting choppy calls at 6 Kbps with double buffering enabled might move up to this triple-buffered option to further smooth the audio.