I Can't generate subtitles from audio V20 b4

I Can't generate subtitles
V20 beta4
macOS
Highlight VO Clips - select menu - Timeline, AI Tools, Generate subtitles from audio -
Prompt comes up, I select 35 characters, 1 line and click create
I progress bar comes up, it seems to have done it and I see no subtitles.
I have tried with a pre-created blank subtitle track and without...

I have done this before in previous versions.
Am I missing something?

I appreciate any feedback.
Cheers

For those who might be interested.

For the time being I am working on an older iMac 2019 intel processor.
This cpu does not create subtitles.

I opened the same project on a newer imac 2021 M1 and it generated the subtitles.

Cheers