Index: uspace/lib/pcm/src/format.c
===================================================================
--- uspace/lib/pcm/src/format.c	(revision aef1799dcd59babab0958fc2cb9766f3c45e8eb3)
+++ uspace/lib/pcm/src/format.c	(revision 82e40051dfb0603c7d781c32e14629002ce5d531)
@@ -160,7 +160,7 @@
 		for (unsigned j = 0; j < df->channels; ++j) { \
 			const float a = \
-			    get_normalized_sample(dst, src_size, i, j, df);\
+			    get_normalized_sample(dst, dst_size, i, j, df);\
 			const float b = \
-			    get_normalized_sample(src, dst_size, i, j, sf);\
+			    get_normalized_sample(src, src_size, i, j, sf);\
 			float c = (a + b); \
 			if (c < -1.0) c = -1.0; \