Your  dynbook USB-C Dock [ Model Part Number: PA5356* ] might intermittently show external video output issues.

When this happens:

• Monitor connected to the USB-C dock will repeatedly flash off and on, while directly connected screens or the built in laptop screen, continue to work
• External monitor connected to the dock is might showing a blank or corrupted image after the Computer return from standby mode

                         
                                                                                                                                   dynabook USB-C Dock Infographic

 
In order to resolve one or more of the described issues, please apply the below USB-C dock firmware package v1.0.0.1.

The firmware update tool as well as an instruction- and installation guide can be found below.

The firmware v1.0.0.1 [TCH1147700A] described in this document is resolving potential issues, where an external monitor connected to the dock is might showing a blank or corrupted image after the Computer return from standby mode.

  IMPORTANT NOTE:

          Dynabook recommend applying in addition the firmware v1.0.4.0 which can be found here.
          
          Firmware v1.0.4.0 is updating the USB hub controller.
          [ Resolving potential USB-C dock LAN connection issues ]

          Furthermore, Dynabook strongly recommend applying the Realtek LAN driver for USB update package [can be found here] as well as the Computers BIOS and graphics card driver to the latest available versions in any case.
          Click here to open the BIOS download page, to obtain the latest available version. To search the latest available graphics card driver, please click here.

 WARNING INSTRUCTION:

         Please read these instructions carefully before applying the USB-C dock firmware update packages.

1. Plug the AC adaptor to the dock and connect dock to Computer with USB-C cable. Make sure the dock is detected by the Computer.
2. Please make sure the dock remains plugged into the Computer during firmware flashing, disconnecting the dock during flashing may cause dock hardware failure.
3. Ensure the PC is in normal working mode during firmware updating. Do not power off or enter sleep mode.
4. Please remove any USB devices before executing the firmware update.

   DYNABOOK USB-C DOCK PA5356
         Firmware  1.0.0.1   [ TCH1147700A ]

•  Change Note:
    1.) Resolving potential issues, where an external monitor connected to the dock is might showing a blank or corrupted image after the Computer return from standby mode.
    2.) Firmware update tool cannot be executed on TigerLake based platforms
  
• Firmware Update Tool Info:        
  Dynabook USB-C Dock (PA5356) Firmware Update Tool Version: 1.0.0.1
  
• File Download:
  
  
  
• Firmware v1.0.0.1 Update Guide:
  
  

  FIRMWARE v1.0.0.1 [TCH1147700A]
        Silent Installation Support

          For silent installation of this firmware update, please extract the package "TCH1147700A.exe" e.g. using 7zip.
          Next, in the folder where the files have been extracted to, locate the folder "MstHub". The executeable 
          "VmmDPTool.exe" / "VmmDPTool64.exe" support the following silent installation command set:

          Usage:    VmmDPTool.exe/VmmDPTool64.exe [-s] [-u] [-v] [-q] [-txxxx.txt] [-gXn] [-ncxx] [-fr] [-fs] [-fd] [-fo] [-fa] [-ixxx.txt] firmware_file_path

 

Silent Installation command set:

-s:      silent action
-u:     update the firmware xxxxx.eeprom/fullrom, the update result will be saved in newer created file update.log
-i:      xxx.txt is file includes all the system ID. Only update the firmware to the laptop which system ID is in the list
-v:     get the current firmware version, the result will be saved on newer created file update.log
-v0:  get the current firmware version and return the version number in bcd format
-t:     Change the txt information show to the user. xxxx.txt is the file name of the txt file

-px:  Change the default folder (current folder) used to save the update.log file
     -p1: save to C:\ProgramData\
     -p2: save to C:\
     -p3: save to C:\Program files
     -p4: save to C:\Windows
     Please note except -p1, the other -p options need run the tool as administrator

-r:    Registry accessing control
     -r0: disable registry access
     -rp: save the result in HKLM\\SYSTEM\\CurrentControlSet\\Control\\MST\\Synaptics permanently

-fr:   force reset hub chip after updating firmware succeed
-fs:  force reboot the system after updating firmware succeed
-fd:  force downgrade the firmware version even firmware version is same or less
-fo:  force override even product ID is not match
-fa:  force search all data path of the GPU, and also search each TX port of the hub to the GPU port.
 
-g:   force connect to the hub with specifc source in case there are more GPUs on system
    The second character is the source type
    The third character is number means the order of the hub if there are more than one hub there. 0 is the default.
    -gA:   AMD only
    -gN:   NVIDIA only
    -gI:     Intel only
    -gI:     Access to the Alternate DDI port of the Intel GPU
    -gW:  WiGig only
    -gG:   graphics only (no WiGig)
    -gX1:  the second hub, here the X can be 'A', 'N', 'I', 'W' or 'G' matching above specific source only.
    -gX2:  the third hub
    By default, the hub is enumerated in the order of Intel, WiGig, Nvidia and AMD

-n:    access to the SYNA hub chip in cascade mode

c is the cascade count

xx is the tx port number cross all the SYNA hub chip, each two bits point to one chip. Bit [c-1:c-2] is the tx port number of first SYNA hub chip connect to GPU side
Below are some examples;
     HSW->hub0 (TX0)->hub1 (TX1)-> hub2->(TX1)->hub3->monitor |--->(TX0)->hub4->monitor
     Access to hub0: -n does not need, or -n00
     Access to hub1:    -n100
     Access to hub2:    -n201
     Access to hub3:   -n305
     Access to hub4:   -n304

firmware_fiel_path here identify where to find the firmware

Note:
The update result will be saved on newer created file update.log, 0 means successful.
The result will be also saved to the registry HKCU\software\Synpatics\PriusTool\ unless use -r0 disable it
The registry value is automatically deleted after system reboot to avoid incorrect information reported

Firmware return code:
 0:   Successful
-1:   unknown error
-3:   AUX write fail
-4:   AUX read fail
0x10:  The firmware is same, no need update
0x11:  Can't downgrade the firmware
0xF2:  The firmware is for different generation chip
0xF3:  The firmware is for different board
0xF4:  Access to VMM chip failed
0xF5:  There is another application tool running
0xF6:  Initialize the GPU library failed
0xF7:  Can't find so many hub devices
0xMMNNBBBB: BCD format of current firmware version return code if -v0 argument is used