diff --git a/src/pulse/stream.c b/src/pulse/stream.c
index b23323d26..73743cbb2 100644
--- a/src/pulse/stream.c
+++ b/src/pulse/stream.c
@@ -2915,7 +2915,7 @@ int pa_stream_set_monitor_stream(pa_stream *s, uint32_t sink_input_idx) {
     return 0;
 }
 
-uint32_t pa_stream_get_monitor_stream(pa_stream *s) {
+uint32_t pa_stream_get_monitor_stream(const pa_stream *s) {
     pa_assert(s);
     pa_assert(PA_REFCNT_VALUE(s) >= 1);
 
diff --git a/src/pulse/stream.h b/src/pulse/stream.h
index 667af8538..7913f7fef 100644
--- a/src/pulse/stream.h
+++ b/src/pulse/stream.h
@@ -801,7 +801,7 @@ int pa_stream_set_monitor_stream(pa_stream *s, uint32_t sink_input_idx);
 /** Return the sink input index previously set with
  * pa_stream_set_monitor_stream(). Returns PA_INVALID_INDEX
  * on failure. \since 0.9.11 */
-uint32_t pa_stream_get_monitor_stream(pa_stream *s);
+uint32_t pa_stream_get_monitor_stream(const pa_stream *s);
 
 PA_C_DECL_END