Sonoma Ventura

Ive got some problems with the Sonoma OS, namely Keynote will no longer play embedded MPG files [garbled audio only] nor will Quicktime play them natively, although VLC continues to play them. I need these presentations for work so cannot afford to wait for a fix. If I use time machine to roll back to pre-Sonoma will this automatically revert to Ventura and hopefully solve my problem? Thank you in anticipation.