Add a subchapter on cue markers

[ardour-manual] / include / latency-and-latency-compensation.html

diff --git a/include/latency-and-latency-compensation.html b/include/latency-and-latency-compensation.html
index f14fc0e917bcc2b59562018251549a8dc00a10d5..59cb28415cb0bb651cf75260922539c3fea1c981 100644 (file)
--- a/include/latency-and-latency-compensation.html
+++ b/include/latency-and-latency-compensation.html
@@ -65,7 +65,8 @@
 <p>
   Processing latency is usually divided into <dfn>capture latency</dfn> (the time
   it takes for the digitized audio to be available for digital processing, usually
-  one audio period), and <dfn>playback latency</dfn> (the time it takes for
+  one audio period), and <dfn>playback latency</dfn> (the time it takes for the
+  audio that has been processed to be available in digital form).
   In practice, the combination of both matters. It is called <dfn>round-trip
   latency</dfn>: the time necessary for a certain audio event to be captured,
   processed and played back.
@@ -260,3 +261,10 @@
   <li>Make the appropriate connections between the jack ports so the loop is closed.</li>
   <li>Adjust the playback and capture levels in the mixer.</li>
 </ol>
+<p class="warning">
+  On Linux, the latency of USB audio interfaces is not constant. It may
+  change when the interface is reconnected, on reboot and even when xruns
+  occur. This is due the buffer handling in the Linux USB stack. As a
+  workaround, it is possible to recalibrate the latency at the start of each
+  session and each time an xrun occurs.
+</p>