Merged revisions 51558 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

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r51558 | file | 2007-01-22 22:00:12 -0500 (Mon, 22 Jan 2007) | 2 lines

Only change audio formats on the channel if we have an audio format to change to. (issue #8535 reported by ivoc)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@51559 65c4cc65-6c06-0410-ace0-fbb531ad65f3