Buffer below 1 second returns error/empty data

[PhiloSolares]

When changing the lsl.outlet buffer size to be below 1 second, LSL fails to send any samples.
Leaving the outlet buffer maximum at 1 second or above, and changing the lsl.inlet buffer size to be below 1 second, keeps pull_sample in what I assume is an indefinite wait loop, and causes pull_chunk to return only empty data. Is 1 second the smallest supported buffer size, or am I missing something?