If you're running code in your NI, the NI master will not report strings via Notifications. If you do not have the device declared in code, and have code associated with parsing strings. The same is true of any device, including RS232/422/485 ports. This relates to legacy RXON/RXOFF usage, which the NI handles automatically when you create an event handler for strings for any device or use the create_buffer keyword.

A simple quick check will be to add the following code:

define_device
dvTP = 11001

define_event
data_event[dvTP]
{
string:
{
}
}

Notifications will now display results from the device.

We also have example code available for review here: VoiceControl for TPControl