Hi Chris, We've had this problem for years, since our database started increasing in size, here's what I do:
Send to schedule, leave the studio empty and make sure no one enters it just in case they touch the pc that is scheduling,
come back into the studio in around 45 minutes, then everything has sorted itself and scheduled nicely.
that way you don't have to watch the non responding wheel spinning which can cause concern, what you don't see can't worry you.
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