RemSound latency lab - measuring depth-target convergence with the shipped playout code.
Raise under test: 30ms -> 330ms. Expected growth at full depth-bias: ~3ms/s.

--- T4 ASIO lane (two-slider mode): ASIO slider drives an ASIO-lane stream ---
  session route after arrival: AsioLane  (slider writes to: AsioLane)
  settled at slider 30ms: buffered=54ms
  t+10s buffered= 289ms
  t+20s buffered= 308ms
  t+30s buffered= 311ms
  t+40s buffered= 303ms
  t+50s buffered= 322ms
  t+60s buffered= 299ms
  RAISE via slider: 54ms -> 299ms in 60s = 4.08ms/s  GROWS (slider works)
  LOWER via slider: back to 30ms -> buffered=30ms after 3s


=== SUMMARY ===
  T4 ASIO lane (two-slider mode): ASIO slider drives an ASIO-lane stream: raise 4.08ms/s [GROWS (slider works)], lower -> 20ms
