Issue with slow speech-to-text captions

I'm messing around with the speech-to-text caption element to create some automated captions and it just will not finish the process of actually producing the captions.

I loaded a simple one minute clip onto the timeline and ran the automatic transciption. It worked great, and very quickly. However, when I click on "Create Captions", it takes me to the captions panel, and shows the "Creating captions..." dialogue with the grey progress bar underneath, but the bar never actually moves. It never makes progress.

I've left it running for a few hours now, and tried multiple different clips/settings and keep running into the same issue. Again, I'm using pretty simple one-minute clips just to give the new feature a trial, and the actual transcription is quick and accurate. Why won't it actually output to a useable captions track?