If you use both WSJT-X and DXLab Suite Commander, you will find that both of these programs need to use the serial CI-V interface to your IC-7300. You cannot use both the native IC-7300 setup for WSJT-X and Commander at the same time.
Fortunately, you can still use both at the same time by selecting the DXLab Suite as the radio selection from the WSJT-X Config screen.
Then run Commander first, followed by WSJT-X. You can even setup DXLab Launcher to do this automatically.
One the big advantages of using DXLab Commander is its ability to show the IC-7300 waterfall spectrum display on you computer monitor. To use this effectively, this means running the serial port at 115200 baud.
If you use the WSJT-X native IC-7300 settings, 19200 is the maximum baud rate you can select. This is because those settings require setting the CV-I USB Port setting to “Link to [REMOTE]” which imposes the 19200 baud limit.
When “Link to [REMOTE]” is selected, the CI-V USB Baud Rate will max out at 19200. There seems to be a bug in the V1.20 IC-7300 firmware that can still show higher baud rates even when “Link to [REMOTE]” is select. But the higher rates don’t work – 19200 is still the maximum. How to recreate this situation is not clear, but it can happen.
On the other hand, the DXLab Suite rig driver needs the CV-I USB Port set to “Unlink from [REMOTE]” which allows it to run at 115200 baud and thus support the waterfall display. This setup will still work correctly with WSJT-X.
DXLab has a page explaining how to setup the waterfall display here.