Remote FT8, Win 10 settings problems

Hi all,

I'm running remote Flex 6700 controlled by Win 7 SP1 laptop not in the same LAN, and have no problems with FT8, CWX, CAT, SSB, DAX, etc, everything works fine.

However, when I want to use another two laptops with Win 10 configurations, I stumble upon these problems:

On one laptop, FT8 TX audio is distorted and I cannot make it looks nice on control waterfall. 
Even if level of TX audio is -20 to -10 dB, signal is 150-200 Hz wide and distorted.
DAX TX level is about 50%, PWR level in JTDX is about 75% adjusted to show TX audio level "in green", less then -10 dB. Radio mode is DIGI-U.

On another laptop, I can't even transmit. When I hit "Tune" in JTDX, TX starts but drops after 1 second or less. The same happens with WSJT-X.
After some hit-and-try, even RX DAX channel 1 stopped to respond.

The same happens with 10W and with 300W (by PGXL).

Restart of DAX, radio didn't help.
First laptop with Win 7 SP1 still controls radio flawlessly. 

Any idea?

Regards,
Dragan, 4O4A