This read-write INTEGER selects the jitter buffer mode for a call connection: fixed (constant size defined by vismJitterInitialDelay) or adaptive (the DSP picks the optimal size). This lets an admin choose between predictable, consistent buffering delay and dynamically optimized buffering that adapts to actual network jitter conditions. For example, on a network path with highly variable jitter, an admin would prefer adaptive mode so the DSP can adjust the buffer size as conditions change, rather than risk a fixed buffer being too small or unnecessarily large.