Interesting thread to follow as I have a similar problem with the Anans when using SDRC VAC/VB Cables, WSJT-x/JTDX.

It only happens with SDRC and not with Thetis or PWRSDR.

I cannot hear it at my end OR if I record the audio using the record button in the TX DSP and play it back.

I cannot hear it over my speakers when I TX.

I have tried multiple Anan radios.

I have tried multiple computers.

I think I can see it on the Pure Signal plots in SDRC. This is why I tried a 10e too,

Receiving stations hear it very clearly which is obviously how I first found out about it.

They hear it when I am using any Digi mode via WSJT-x/JTDX via Vac BUT they also hear it 

when I use the TONE or TUNE button on the TX DSP in SDRC.

My intention was to have one of the RXing stations record their end so I can send it as an attachment.

I will follow this thread and make test changes as recommended.

I will use a set up with no internet and just CAT5 connection to the Anan.

If I have no luck I will try to document it better and ask more questions.

Thank You.

Paul N2EME