"The main improvements can be found under the hood of the audio engine," Skype spokesman Villu Arak wrote in his blog.
Another upgrade to the 184.108.40.206 version eliminates the need to adjust the sound settings after changing headsets or microphones, Arak wrote. Some video-related bugs have also been cleared up, and the client now has its own implementation of the Universal Plug-and-Play networking protocol, rather than relying on Microsoft's code.
Also, Skype 3.8 will by default not show an avatar when a user sees an incoming authorization request.
"Some people have been using offensive images, so we decided to put them behind a veil," Arak wrote. "You can still see the hidden avatar if you click on it.
Skype was bought by eBay in 2005 for US$2.6 billion. While the subsidiary is profitable as well as popular, it has been pressured by heavy competition from operators and other VOIP (voice over Internet Protocol) services.
Speculation abounded Skype might be sold after eBay executives said earlier they were taking a look at how to work Skype better into their business. So far, no sale has materialized.
Earlier this month, Skype introduced a flat-rate international calling plan with up to 10,000 minutes per month. For U.S. users, the plan costs $9.95 for calls to 34 countries.