3 files changed, 44 insertions, 0 deletions
diff --git a/src/output/Source.cxx b/src/output/Source.cxx
index d6c110a38..fdaff77f2 100644
--- a/src/output/Source.cxx
+++ b/src/output/Source.cxx
@@ -244,3 +244,11 @@ AudioOutputSource::ConsumeData(size_t nbytes) noexcept
 	if (pending_data.empty())
 		pipe.Consume(*std::exchange(current_chunk, nullptr));
 }
+
+ConstBuffer<void>
+AudioOutputSource::Flush()
+{
+	return filter
+		? filter->Flush()
+		: nullptr;
+}
diff --git a/src/output/Source.hxx b/src/output/Source.hxx
index 1b26a3378..435ce52b2 100644
--- a/src/output/Source.hxx
+++ b/src/output/Source.hxx
@@ -195,6 +195,11 @@ public:
 		pipe.ClearTail(chunk);
 	}
 
+	/**
+	 * Wrapper for Filter::Flush().
+	 */
+	ConstBuffer<void> Flush();
+
 private:
 	void OpenFilter(AudioFormat audio_format,
 			PreparedFilter *prepared_replay_gain_filter,
diff --git a/src/output/Thread.cxx b/src/output/Thread.cxx
index ac382864a..bad9e0a73 100644
--- a/src/output/Thread.cxx
+++ b/src/output/Thread.cxx
@@ -362,11 +362,42 @@ AudioOutputControl::InternalPause() noexcept
 	skip_delay = true;
 }
 
+static void
+PlayFull(FilteredAudioOutput &output, ConstBuffer<void> _buffer)
+{
+	auto buffer = ConstBuffer<uint8_t>::FromVoid(_buffer);
+
+	while (!buffer.empty()) {
+		size_t nbytes = output.Play(buffer.data, buffer.size);
+		assert(nbytes > 0);
+
+		buffer.skip_front(nbytes);
+	}
+
+}
+
 inline void
 AudioOutputControl::InternalDrain() noexcept
 {
 	const ScopeUnlock unlock(mutex);
 
+	try {
+		/* flush the filter and play its remaining output */
+
+		while (true) {
+			auto buffer = source.Flush();
+			if (buffer.IsNull())
+				break;
+
+			PlayFull(*output, buffer);
+		}
+	} catch (...) {
+		FormatError(std::current_exception(),
+			    "Failed to flush filter on %s", GetLogName());
+		InternalCloseError(std::current_exception());
+		return;
+	}
+
 	output->Drain();
 }