BM hardware could not be found in your system (Ubuntu 18)

Error message graphical interface for Media Express: BM hardware could not be found in your system
-please check the installation

BM Tech support:
The error message: Blackmagic hardware could not be found in your system indicates that there is another software that is currently using the Mini Recorder. Be sure to close other application as the Mini Recorder can only be used in one program at a time.

Hardware install:
I have installed two BM mini recorder on Ubuntu 18.
The first one broke and returned to amazon.
I got a replacement and installed it.

I need help with:
-Provide help in how to close applications on Ubuntu 18.

install hardware details:
Ubuntu 18.04.1 LTS set up on Dell Optiplex 760
8GB Ram with Samsum SD
Processor: Intel Core 2 Doue CPE E8600 @ 3.33GHZ x2
Intel Q45/Q43
GNOME 3.28.2
OS type: 64-bit


Graphical System information: PCI Devices
Multimedia video controller
BM Desing DeckLink Mini Recorder

Terminal information
:~$ dpkg -l | grep -i blackmagic
ii desktopvideo 10.11.4a9 amd64 Blackmagic Design Desktop Video 10.11.4 - Driver and Firmware Update utility
ii desktopvideo-gui 10.11.4a9 amd64 Blackmagic Design Desktop Video 10.11.4 - GUI Utilities
ii desktopvideo-scanner 10.11.4a9 amd64 Blackmagic Design Desktop Video 10.11.4 - Cintel Scanner driver
ii mediaexpress 3.5.7a5 amd64 Blackmagic Design Media Express 3.5.7