Should latency numbers add up to total latency?

[Hans Peter Augustesen]

Here are some numbers from a duo session (Session Diagnostics & Stats):

1. person:

Total Latency: 22 ms

Audio Interface

Latency 4.2 ms
Input Jitter 0.48 ms
Output Jitter 0.42 ms
Frame Size 2.5 ms

Internet

Latency 13.0 ms
Jitter Queue 2.0
Jitter 0.7 ms

Audio Bw Rx 509 k
Audio Bw Tx 451 k


2. person:

Total Latency: 22 ms

Audio Interface

Latency 4.2 ms
Input Jitter 0.23 ms
Output Jitter 0.23 ms
Frame Size 2.5 ms

Internet

Latency 13.0 ms
Jitter Queue 4.2
Jitter 2.9 ms

Audio Bw Rx 430 k
Audio Bw Tx 525 k
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As can be seen, both audio interface latency is 4.2 ms and internet latency is 13 ms.
Together it gives 21.4.
It is close to the 22 ms total latency.

But what about the other numbers?
Frame Size e.g. is a total of 5 ms.

It does not fit if these 5 ms are to be added.

And there are the other values ​​as well.

So how does the whole calculation go up?