AVB-DC: Can I run a variable sampling rate Listener?

[TomRSI]

Hello,

I am developing a 4CH listener and 4CH talker application that will run any sampling frequency from 32kHz up to, at least, 96kHz. As an audio interface I use a TDM protocol, which is based on the I2S example. The Audio interface is working quite well with my TDM interface (i know there is a new TDM interface on the XMOS repository but that came up after I had mine working).
Now I am trying to get a Listener only (simlifying the problem) which run at any sampling frequency the master (talker) runs at. For this purpose I am using a AVB-DC kit (where my listener is not using an audio pll board but has a custom board with a CS2300). I am using last software release of this application.
I have seen that the low frequency clock recovered from the network (media clock) goes from 960Hz to 1.92kHz when the default_sample_rate in the application_task (main.xc) goes from 48000 to 96000. Reading in the documentation, I have noticed that the media clock is given by a master which is chosen by a clock quality criteria.
My question would be: The PTP server (which generates the media clock which ends in the PLL_SYNC signal that allows the PLL to generate the MCLK and correct my if I am wrong) can run always as a slave? In that case, can it generate a clock derived from the sampling rate in the Master? and last one, why there is a default_sample_rate on the main code that configures the media clock, shoould that no purely derived from the media clock in the AVB tile?

thanks in advance,

Tomás.

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