I couldn't find anything in the manual about a 2 gig limit.
I just found these two items.
8. Record Time Available: . . . . This is not an adjustable parameter—it merely shows the space available on the media in the
MicroTrack 24/96. When you select this option, it may take a moment to calculate the available
time and display on the screen. This information is provided to help you verify you will have
enough recording space before recording, and make a choice of which recording parameters to
use. If you see that you’re getting low on memory space, you can choose to use MP3 encoding
instead of WAV to yield smaller recordings. Keep in mind this feature only accounts for recording
space when determining record time—it does not account for battery life.