DAX Audio over SmartLink choppy...

ok2it

Hello I know this has been asked before but I am struggling a lot. I am network engineer by trade, and I tried everything from IPSec/L2TPv3 , VPNs with low latency but I am not getting anywhere. I am travelling and WPX RTTY is on but I can onsly SWL as my TX signal is just dirty...not dirty TX but audio is distorted, chopped, and it looks like lot of packets are lost, altough if I use Virtual Audio Cables, all works fine. This seems to be somehow bound to DAX Audio only.
https://ctrlv.link/TTtG
That is screenshot and I am also listening to MON and sounds horrible. Tried single tone, two tone test on TX same results, regardless of TX Levels. Works fine locally, but even if I go just to next internet conenction (I have 2 x FTTH 1000mbps lines on my remote QTH) and I go from one to another, with latency bellow 25mS constant, zero jitter buffer needed, it happenes as well.
I saw suggestion to reboot do radio, done that, it helped for a minute or two and then started all over again. I also seem to remember it got worse as I moved up the FW. Currently sitting at 3.6.8 as I tried 4, but didnt work with iOS APPs I am using and I lost Waveforms for FreeDV.

Runnig Flex 6300 baby, v3, using Extreme Networks infrastructure. Any hints?

Thanks Jiri OK2IT