diff --git a/libretro-common/audio/dsp_filters/tremolo.c b/libretro-common/audio/dsp_filters/tremolo.c
index 5bdf52ed32..c7a5d6a143 100644
--- a/libretro-common/audio/dsp_filters/tremolo.c
+++ b/libretro-common/audio/dsp_filters/tremolo.c
@@ -35,8 +35,8 @@ struct tremolo_core
    float *wavetable;
    float freq;
    float depth;
-   int index;
-   int maxindex;
+   unsigned index;
+   unsigned maxindex;
 };
 
 struct tremolo