Linux Mint Forums

I found this resource with a google search of "ubuntu 8.10 skype problem with audio playback".
http://www.econowics.com/news-from-the- ... epid-ibex/
It might be of help, google is your friend as well and I think this is a fairly well-documented problem.

Before you do anything, under Skype Options -> Sound Devices. What do you have listed for sound in, out, and ringing?