Keyspan USA-19 - Manual (Page 36)

Click on the Device Control Presets tab. (see below)
Select your deck from the list and click on edit. This will bring up the Device Control Preset
Editor. (see below)
Keyspan:USB Serial Adapter for Mac OS X-v2.x User Manual
This User Manual applies to the Keyspan USB Serial Adapter Software for Mac OS X.
Rev 05jul15 Page 36