fix garbage audio getting sent to surround sound channels

Author: tesselode

changelog.md

@@ -3,6 +3,7 @@
 - Fix `kira::spatial::scene::AddEmitterError` not being publicly available
 - Fix some typos in the documentation
 - Add the `assert_no_alloc` feature
+- Fix garbage audio getting sent to surround sound channels
 
 # v0.8.4 - June 19, 2023
 

crates/kira/src/manager/backend/cpal/desktop/stream_manager.rs

@@ -196,6 +196,14 @@ fn process_renderer(renderer_wrapper: &mut RendererWrapper, data: &mut [f32], ch
 		} else {
 			frame[0] = out.left;
 			frame[1] = out.right;
+			/*
+				if there's more channels, send silence to them. if we don't,
+				we might get bad sounds outputted to those channels.
+				(https://github.com/tesselode/kira/issues/50)
+			*/
+			for channel in frame.iter_mut().skip(2) {
+				*channel = 0.0;
+			}
 		}
 	}
 }