I think OBDLink SX default baud rate is 115200, but it can be configured to something else.

With RealDash closed, plugging in the adapter, does the system popup appear offering RealDash to be used with? Or does RealDash boot automatically as soon as USB is plugged in?

once I connect the USB it boots real dash automatically.

Ok, that indicates that RealDash has permission to use the adapter. Then I’m out of ideas. We do have OBDLink SX that we use for testing purposes almost daily.