I was wondering if the Creative Commons Attribution-Share Alike licenses expects software that uses it to be distributed under a copyleft software license. Does it make a difference if the media is just linked and can be changed or if the media is embedded inside the software?
Bonus questions: Would the GPL conflict with the Creative Commons licenses' attribution requirement? Is it a good idea to distribute media under a free software license?
Yes. It's Share-Alike. This means that it has to be under a compatible free license which allows similar freedoms. Usually this is also CC.
At a minimum, the CC-SA license says you must provide attribution and a link to the work's CC license. Whether or not distribution in your software would fall under "alter, transform, or build upon this work" is best left to a lawyer - depending on the case, it might be considered a "Collection" or simply permissible distribution. Your best bet is to just contact the owner and ask.
Just as CC explicitly says "don't use CC for software", software licenses should not be used for non-software.
I'm assuming you're talking about mp3, or mpeg or similar work that's under the CC, while using it in say a game.
I think in that case, you're probably ok, as long as you give full credit etc in the game somewhere. Preferably somewhere prominent, where the author benefits as well as you.