diff --git a/src/MusicChunk.cxx b/src/MusicChunk.cxx
index 784a27785..cc2de38a1 100644
--- a/src/MusicChunk.cxx
+++ b/src/MusicChunk.cxx
@@ -36,7 +36,7 @@ MusicChunkInfo::CheckFormat(const AudioFormat other_format) const noexcept
 }
 #endif
 
-WritableBuffer<void>
+std::span<std::byte>
 MusicChunk::Write(const AudioFormat af,
 		  SongTime data_time, uint16_t _bit_rate) noexcept
 {
diff --git a/src/MusicChunk.hxx b/src/MusicChunk.hxx
index c1a4cf1fd..e9516cfde 100644
--- a/src/MusicChunk.hxx
+++ b/src/MusicChunk.hxx
@@ -23,7 +23,6 @@
 #include "MusicChunkPtr.hxx"
 #include "Chrono.hxx"
 #include "tag/ReplayGainInfo.hxx"
-#include "util/WritableBuffer.hxx"
 
 #ifndef NDEBUG
 #include "pcm/AudioFormat.hxx"
@@ -32,6 +31,7 @@
 #include <cstddef>
 #include <cstdint>
 #include <memory>
+#include <span>
 
 static constexpr size_t CHUNK_SIZE = 4096;
 
@@ -116,7 +116,7 @@ struct MusicChunkInfo {
  */
 struct MusicChunk : MusicChunkInfo {
 	/** the data (probably PCM) */
-	uint8_t data[CHUNK_SIZE - sizeof(MusicChunkInfo)];
+	std::byte data[CHUNK_SIZE - sizeof(MusicChunkInfo)];
 
 	/**
 	 * Prepares appending to the music chunk.  Returns a buffer
@@ -129,7 +129,7 @@ struct MusicChunk : MusicChunkInfo {
 	 * @param bit_rate the current bit rate of the source file
 	 * @return a writable buffer, or nullptr if the chunk is full
 	 */
-	WritableBuffer<void> Write(AudioFormat af,
+	std::span<std::byte> Write(AudioFormat af,
 				   SongTime data_time,
 				   uint16_t bit_rate) noexcept;
 
diff --git a/src/decoder/Bridge.cxx b/src/decoder/Bridge.cxx
index a57f8d8cc..d273cde8a 100644
--- a/src/decoder/Bridge.cxx
+++ b/src/decoder/Bridge.cxx
@@ -545,11 +545,11 @@ DecoderBridge::SubmitData(InputStream *is,
 			continue;
 		}
 
-		const size_t nbytes = std::min(dest.size, length);
+		const size_t nbytes = std::min(dest.size(), length);
 
 		/* copy the buffer */
 
-		memcpy(dest.data, data, nbytes);
+		memcpy(dest.data(), data, nbytes);
 
 		/* expand the music pipe chunk */
 
diff --git a/src/pcm/MixRampGlue.cxx b/src/pcm/MixRampGlue.cxx
index fd8e7dfdd..ab1670b0a 100644
--- a/src/pcm/MixRampGlue.cxx
+++ b/src/pcm/MixRampGlue.cxx
@@ -23,6 +23,7 @@
 #include "MusicPipe.hxx"
 #include "MusicChunk.hxx"
 #include "util/Compiler.h"
+#include "util/ConstBuffer.hxx"
 
 #include <stdio.h>