012_add_volume_control.patch

--- src/ao.h	2013-03-14 19:07:04.000000000 +0100
+++ src/ao.h	2013-03-14 20:45:15.000000000 +0100
@@ -141,6 +141,7 @@
 
 #endif  /* __AO_H__ */
 
+#define SHAIRPORT_AUDIOOUTPUT_VERSION 2
 extern struct AudioOutput g_ao;
 struct AudioOutput                                                                                                                                                                                              
   {                                                                                                                                                                                                              
@@ -155,4 +156,5 @@
       char* (*ao_get_option)(ao_option *, const char* );
       void (*ao_set_metadata)(const char *buffer, unsigned int size);                                                                                                                                                         
       void (*ao_set_metadata_coverart)(const char *buffer, unsigned int size);
+      void (*ao_set_volume)(float volume);
   }; 
diff -uPr orig/src/hairtunes.c macosx10.6_i386-target/src/hairtunes.c
--- src/hairtunes.c	2013-03-14 19:07:04.000000000 +0100
+++ src/hairtunes.c	2013-03-14 20:46:33.000000000 +0100
@@ -265,6 +265,8 @@
   assert(f<=0);
   if (debug)
       xprintf("VOL: %lf\n", f);
+  if (g_ao.ao_set_volume)
+    g_ao.ao_set_volume(f);
   volume = pow(10.0,0.05*f);
   fix_volume = 65536.0 * volume;
 }