Free Oxford Advanced Learners Dictionary For Mac

Someone else here may have other suggestions, but I was able to find the following information on Oxford's support site. It may fix your problem, though it doesn't specifically address sound not playing (it does for the Mac version). I'd suggest you keep the old plugin files until you verify that the new plugins don't cause worse problems.
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Q. I have QuickTime 7 for Windows installed. Why do I get an error message 'Quicktime plug-in requires the Quicktime system extension version 5 or later' when starting the OALD7 Compass CD-ROM?
A. The Compass CD-ROM was developed before QuickTime 7 was released, and there are some incompatibilites which can be fixed as follows:
If it is open, close the OALD7 Compass application.
Download the pluginsQT7win.zip patch file
In the directory where OALD7 is installed (usually c:Program FilesOxfordOALD7), there is a directory called plugins - delete all the files in the plugins directory.
Move plugins QT7win.zip into the now empty plugins folder, and unzip the 4 files there.
Sound should now be working - if you have any further problems or queries, please email the helpdesk.
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I hope this helps.
Dave