On Windows, an H224 notification may appear in the lower right corner near the system trey clock. This can be disabled in Windows “Notifications & Actions” panel if it desired.
In Pro Tools First, selecting “Optimize for Recording” sets the audio device buffer size to 64 samples. Selecting “Optimize for Mixing” sets the buffer size to 512 samples. On windows, you can override this with a custom buffer size selection by going to menu Setup >...
This is by design, to avoid audio artifacts H224 gradually changes volume up or down regardless of how quickly volume knob is adjusted on the hardware.
Click the up arrow icon found in the taskbar near the system trey (taskbar clock) to reveal additional app icons. Drag the H224 silver “S” icon next to the taskbar clock so it is always visible.
Verify in windows sound settings that the appropriate H224 outputs are selected. If you speakers are connected to H224 outputs 1, 2, then select “Speakers H224 Audio Driver” (which is H224 outputs 1,2).