On points:
At me on the xfce server

Sound:
The sound earned. audioout=list helped to see the correct name of the alsa_card.pci-0000_00_1b.0|output:analog-stereo sound card But a sound every time of mute. It is necessary to include it.

Usb disks:
I tried 3 usb flash drive. On all there is a file system and they are workers. Did everything in the console of the thin client (ctrl alt f1 user/live)

mount | tee mountbefore
then insert the USB flash drive
mount | tee mountafter
diff mountbefore mountafter
Output blank line (there is no difference between files)

At the same time at connection of usb it is displayed nothing in the console. Only at connection of one device in the console appears
sd 6:0:0:0 [sda] No Caching mode page found
sd 6:0:0:0 [sda] Assuming drive cache: write through

If in the console of the thin client to execute udevadm monitor - property - kernel - udev, then at connection of any flash drive outputs a lot of information on the attached device (model, serial number, vendor and many other things)

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