Does music under CC-SA license require the same license for video?
From the by-sa legal terminology:


  Section 1 – Definitions.
  
  Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.


In other words, using it as a sound track in a video makes the video a derivative work and requires share-alike unless that provision of the license is unenforceable in your local jurisdiction.  (ie, still see a lawyer, but you most likely must share alike the video.)