HighSierra 10.13.3 USB-Kernel-Modul or Subsystem of MacOSX sometimes dies until reboot

Using the UR22mkII
The latest USB Driver for High Sierra 10.13 http://download.steinberg.net/downloads_hardware/Yamaha_Steinberg_USB_Driver/Mac/1.9.10-2/YSUSB_V1910-2_Mac.zip
solved an issue I had for nearly a year (need to switch back an forth the sample rate each time I plugged in the UR22mkII)
this issue was fixed for 4 weeks or so…
Until the HighSierra Update 10.13.3 made it even worse: now sometimes (around 1 of 4 USB plug-ins) the USB-Kernel-Modul or Subsystem of MacOSX gets screwed up,
my MacBook has 2 USB3 Ports. So when one port is dead, I can use the other one until its dead too.
Then I have to reboot the MacBook to get this fixed each time.

Anyone else with this problem?
EDIT:
found out this:
when the UR22mkII is unplugged, the USB Driver driver is not always unloaded as it should. It sometimes still shows up in MacOS Systeminformation -> Systemreport>Hardware->USB. It should not be displayed here, when unplugged, right?:


and

When the UR22mkII is UNPLUGGED, and I try to

sudo kextunload -v 6 -b jp.co.yamaha.driver.YamahaSteinbergUSBAudio
i got:
Kext user-space log filter changed from 0xff2 to 0xfff.
Kext kernel-space log filter changed from 0xff2 to 0xfff.
Requesting unload of jp.co.yamaha.driver.YamahaSteinbergUSBAudio (with termnation of IOServices).
(kernel) User-space log flags changed from 0x0 to 0xfff.
(kernel) Received ‘Unload’ request from user space.
(kernel) Can’t unload kext jp.co.yamaha.driver.YamahaSteinbergUSBAudio; classes have instances:
(kernel) Kext jp.co.yamaha.driver.YamahaSteinbergUSBAudio class YamahaUSBAudioEngine2 has 1 instance.
(kernel) Kext jp.co.yamaha.driver.YamahaSteinbergUSBAudio class YamahaUSBAudioStream2 has 2 instances.
(kernel) Kext jp.co.yamaha.driver.YamahaSteinbergUSBAudio class YamahaUSBAudioOutputStream has 1 instance.
(kernel) Kext jp.co.yamaha.driver.YamahaSteinbergUSBAudio class YamahaUSBAudioInputStream has 1 instance.
Kernel error handling kext request - (libkern/kext) kext is in use or retained (cannot unload).
Failed to unload jp.co.yamaha.driver.YamahaSteinbergUSBAudio - (libkern/kext) kext is in use or retained (cannot unload).

which should not happen.
als opposed to immediately after reboot:

Last login: Sat Feb 10 21:10:21 on console
Bodos-MBP:~ bodo$ sudo kextunload -v 6 -b jp.co.yamaha.driver.YamahaSteinbergUSBAudio
Password:
Kext user-space log filter changed from 0xff2 to 0xfff.
Kext kernel-space log filter changed from 0xff2 to 0xfff.
Requesting unload of jp.co.yamaha.driver.YamahaSteinbergUSBAudio (with termnation of IOServices).
(kernel) User-space log flags changed from 0x0 to 0xfff.
(kernel) Received ‘Unload’ request from user space.
(kernel) Kext jp.co.yamaha.driver.YamahaSteinbergUSBAudio removing all personalities naming it from the IOCatalogue.
Successfully unloaded jp.co.yamaha.driver.YamahaSteinbergUSBAudio.
jp.co.yamaha.driver.YamahaSteinbergUSBAudio unloaded and personalities removed.
Bodos-MBP:~ bodo$ sudo kextload -v 6 -b jp.co.yamaha.driver.YamahaSteinbergUSBAudio
Kext user-space log filter changed from 0xff2 to 0xfff.
Kext kernel-space log filter changed from 0xff2 to 0xfff.
Requesting load of jp.co.yamaha.driver.YamahaSteinbergUSBAudio.
jp.co.yamaha.driver.YamahaSteinbergUSBAudio loaded successfully (or already loaded).
Bodos-MBP:~ bodo$