speaker icon

git-svn-id: https://lmuse.svn.sourceforge.net/svnroot/lmuse/trunk@1673 21394207-e112-0410-bd00-e4265ec52c78
deduplicated AudioTrack::{copy,add}Data


git-svn-id: https://lmuse.svn.sourceforge.net/svnroot/lmuse/trunk@1674 21394207-e112-0410-bd00-e4265ec52c78