Index: uspace/drv/audio/sb16/dma_controller.c
===================================================================
--- uspace/drv/audio/sb16/dma_controller.c	(revision d2134da35e1d3328a36a241bd870630d2e366edc)
+++ uspace/drv/audio/sb16/dma_controller.c	(revision aa5ae788d2d3f4f0d6655478226f4fcdb817764f)
@@ -240,5 +240,5 @@
     unsigned channel, uintptr_t pa, size_t size)
 {
-	if (channel == 4 || channel > 7)
+	if (channel <= 4 || channel > 7)
 		return ENOTSUP;
 	assert(controller);
@@ -286,7 +286,9 @@
 	if (!controller)
 		controller = dma_controller_init();
+
 	if (!controller)
 		return EIO;
-	if (channel <= 4)
+
+	if (channel < 4)
 		return dma_setup_channel_8bit(controller, channel, pa, size);
 	else