diff --git a/libs/audio/source/effect/fade_out.cpp b/libs/audio/source/effect/fade_out.cpp
index 335995f8..34440932 100644
--- a/libs/audio/source/effect/fade_out.cpp
+++ b/libs/audio/source/effect/fade_out.cpp
@@ -16,12 +16,12 @@ namespace psemek::audio
 				: stream_(std::move(stream))
 				, length_(length)
 				, start_(start)
+				, total_length_(stream_->played() + start_.samples() + length_.samples())
 			{}
 
 			std::optional<std::size_t> length() const override
 			{
-				// TODO: compute fade_out length using the number of samples already played
-				return stream_->length();
+				return total_length_;
 			}
 
 			std::size_t played() const override
@@ -62,6 +62,7 @@ namespace psemek::audio
 			duration length_;
 			duration start_;
 			std::size_t current_ = 0;
+			std::size_t total_length_ = 0;
 		};
 
 	}