diff --git a/ext/soundtouch/gstpitch.cc b/ext/soundtouch/gstpitch.cc
index 9ab0d1d7f5..3853802a06 100644
--- a/ext/soundtouch/gstpitch.cc
+++ b/ext/soundtouch/gstpitch.cc
@@ -73,13 +73,13 @@ enum
     "audio/x-raw, " \
       "format = (string) " GST_AUDIO_NE (F32) ", " \
       "rate = (int) [ 8000, MAX ], " \
-      "channels = (int) [ 1, 2 ]"
+      "channels = (int) [ 1, MAX ]"
 #elif defined(SOUNDTOUCH_INTEGER_SAMPLES)
   #define SUPPORTED_CAPS \
     "audio/x-raw, " \
       "format = (string) " GST_AUDIO_NE (S16) ", " \
       "rate = (int) [ 8000, MAX ], " \
-      "channels = (int) [ 1, 2 ]"
+      "channels = (int) [ 1, MAX ]"
 #else
 #error "Only integer or float samples are supported"
 #endif