diff --git a/release-packaging/Classes/FluidCorpusBuilders.sc b/release-packaging/Classes/FluidCorpusBuilders.sc
index d6698b3..5feb958 100644
--- a/release-packaging/Classes/FluidCorpusBuilders.sc
+++ b/release-packaging/Classes/FluidCorpusBuilders.sc
@@ -150,7 +150,7 @@ FluidProcessSlices{
 			{
 				var numframes,feature;
 				numframes = v[\bounds].reverse.reduce('-');
-				feature = featureFunc.value(sourceBuffer, v[\bounds][0],numframes,idx);
+				feature = featureFunc.value(sourceBuffer, v[\bounds][0],numframes,k);
 				SendReply.kr(Done.kr(feature),'/doneFeature' ++ uid ++ idx);
 				FreeSelfWhenDone.kr(feature);
 			}.play(server);