diff --git a/libavcodec/dcadsp.c b/libavcodec/dcadsp.c
index 4f1e933cfb..fade1a6c02 100644
--- a/libavcodec/dcadsp.c
+++ b/libavcodec/dcadsp.c
@@ -320,7 +320,7 @@ static void dmix_sub_c(int32_t *dst, const int32_t *src, int coeff, ptrdiff_t le
     int i;
 
     for (i = 0; i < len; i++)
-        dst[i] -= mul15(src[i], coeff);
+        dst[i] -= (unsigned)mul15(src[i], coeff);
 }
 
 static void dmix_add_c(int32_t *dst, const int32_t *src, int coeff, ptrdiff_t len)