Hello there,  @patbridgetgrave  Welcome to the Canvas Community.  Thank you for posting your question.  I'm not a real expert on this topic, but I searched the Community (How do I search and filter content in the Canvas Community?) for similar topics, and I found the following that may be of help:

• How to add powerpoints with sound?
• How do upload a power point with sound
• how do i import a PPTx file with sound files imbeded into a module so that students will actually he...

I hope these resources will be of help to you, Bridget.  Please sing out if you have any other questions about this.