diff --git a/spa/include/spa/param/audio/raw.h b/spa/include/spa/param/audio/raw.h
index 47425ab5f..457b09919 100644
--- a/spa/include/spa/param/audio/raw.h
+++ b/spa/include/spa/param/audio/raw.h
@@ -18,7 +18,11 @@ extern "C" {
  * \{
  */
 
+/* This is the max number of channels, changing this will change the
+ * size of some helper structures. This value should be at least 64 */
+#ifndef SPA_AUDIO_MAX_CHANNELS
 #define SPA_AUDIO_MAX_CHANNELS	64u
+#endif
 
 enum spa_audio_format {
 	SPA_AUDIO_FORMAT_UNKNOWN,