No sound on PowerPoint shows

There's plenty on this topic on various forums but it's mostly a few years old, and no real, free solution seemed to have been identified? On my iMac with Lion and the latest version of OpenOffice installed, I can view PowerPoint shows (.pps files) in either Preview or OpenOffice but I can get no sound. Sound is embedded in the files and plays OK on a Windows XP laptop - there is no problem with the files. Has anyone found a solution to this problem that doesn't involve buying Office for Mac or iWorks?

Why don't you download a trial version of MS Office 2011 for the Mac from Microsoft and see if your Powerpoint files work OK. Also, the iWork version (Keynote) is only $19.99 from the App store.

Open Office and LibreOffice both do not work well to reproduce the sound and transitions from Powerpoint. Keynote should work a lot better, however, there are some things from Powerpoint that will not work as well in Keynote either.

Thanks for those suggestions CHSCAG. I thought that, before I spent money contributing to MS's profits, I would make doubly sure that none of the program's currently on my iMac would produce sound from .pps files. I tried OpenOffice again and found a small button for playing the slideshow. To my surprise and pleasure, it played the file perfectly with the right sound. Must have a beer with all the money I have saved!