Yes, a second element "powerful" seems more plausible than the "journey" that I had so far in my own database.
The Gothic word is swinþs "strong". The English word sound in the sense of "healthy" and the German word geschwind for "fast" have the same root:
http://www.nordicnames.de/wiki/SWINDhttp://www.etymonline.com/index.php?term=sound