diff --git a/src/pulse/stream.c b/src/pulse/stream.c
index d57c27ad9..b23323d26 100644
--- a/src/pulse/stream.c
+++ b/src/pulse/stream.c
@@ -2570,7 +2570,7 @@ const pa_channel_map* pa_stream_get_channel_map(pa_stream *s) {
     return &s->channel_map;
 }
 
-const pa_format_info* pa_stream_get_format_info(pa_stream *s) {
+const pa_format_info* pa_stream_get_format_info(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 1c2283545..667af8538 100644
--- a/src/pulse/stream.h
+++ b/src/pulse/stream.h
@@ -751,7 +751,7 @@ const pa_sample_spec* pa_stream_get_sample_spec(pa_stream *s);
 const pa_channel_map* pa_stream_get_channel_map(pa_stream *s);
 
 /** Return a pointer to the stream's format. \since 1.0 */
-const pa_format_info* pa_stream_get_format_info(pa_stream *s);
+const pa_format_info* pa_stream_get_format_info(const pa_stream *s);
 
 /** Return the per-stream server-side buffer metrics of the
  * stream. Only valid after the stream has been connected successfully