RME Audio AVB Tool, Руководство пользователя

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If the digital outputs of networked devices should to be phase aligned, is necessary to choose a value
that is a multiple of a sample length (1 second divided by sampling rate). For example, given a
requirement of 1ms latency with a sampling rate of 44100 Hz: calculate the number of samples for the
given latency (in this example, 44.1 samples), and then multiply the rounded value (44) with the sample
length (1s/44100). Rounded to the next 100ns, the result is 997700ns.
Table 1. Recommended presentation time offsets < 2ms, in nanoseconds
Rate 2ms 1ms 0.6ms 0.3ms
44100 1995500 997700 634900 317500
48000 2000000 1000000 625000 312500
88200 1995500 997700 623600 317500
96000 2000000 1000000 625000 312500
176400 2001100 997700 623600 311800
192000 2000000 1000000 625000 312500

The RME Digiface AVB shows the remaining offset ("input delay") for the first incoming
stream, which is useful to verify that a shorter setting for the existing network can be used
without risking dropouts.
The AVB Tool offers a freely adjustable presentation time offset for each output stream.

In AVB networks, the latency is always specified by the talker and guaranteed by the
listener. This behavior is
plug and play and does not require any user interaction or
monitoring.
5.4.1. Adjusting the Network Latency
The default presentation time offset of 2 ms for outgoing streams can be changed when lower latencies
are required.
This setting can only be accessed on the web remote (see Finding the Device on a Network]), where it
can be found in the outgoing stream settings.

Changing the presentation time offset briefly interrupts all incoming and outgoing AVB
streams.
RME AVB Tool User’s Guide
5.4. AVB Network Latency | 24