One of our users says audio runs fast

I have a Captivate 4 lesson that has been running on an LMS for a number of months with no issues. The other day a user called and said the audio was running fast (like the chipmunks). He said he tried another computer in his office and got the same thing. This has not happend before and no one else has reported this problem. Has anyone else had a problem like this? What do I tell the user?

Thanks,

Dave