diff --git a/fmp/fmp_chunk.go b/fmp/fmp_chunk.go
index 96d4b83..c94be12 100644
--- a/fmp/fmp_chunk.go
+++ b/fmp/fmp_chunk.go
@@ -6,178 +6,177 @@ func (ctx *FmpFile) readChunk(payload []byte) (*FmpChunk, error) {
 	// https://github.com/Rasmus20B/fmplib/blob/66245e5269275724bacfe1437fb1f73bc587a2f3/src/fmp_format/chunk.rs#L57-L60
 
 	chunk := &FmpChunk{}
+	chunkCode := payload[0]
 
-	if (payload[0] & 0xC0) == 0xC0 {
-		payload[0] &= 0x3F
+	if (chunkCode & 0xC0) == 0xC0 {
+		chunkCode &= 0x3F
 		chunk.Delayed = true
 	}
 
-	switch payload[0] {
+	switch chunkCode {
 	case 0x00:
-		chunk.Type = FMP_CHUNK_SIMPLE_DATA
-		chunk.Value = payload[1 : 1+1]
 		chunk.Length = 2
+		chunk.Type = FMP_CHUNK_SIMPLE_DATA
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x01:
+		chunk.Length = 3
 		chunk.Type = FMP_CHUNK_SIMPLE_KEY_VALUE
 		chunk.Key = uint64(payload[1])
-		chunk.Value = payload[2 : 2+1]
-		chunk.Length = 3
+		chunk.Value = payload[2:chunk.Length]
 
 	case 0x02, 0x03, 0x04, 0x05:
-		valueLength := uint64(2 * (payload[0] - 1))
+		valueLength := uint64(2 * (chunkCode - 1))
+		chunk.Length = 2 + valueLength
 		chunk.Type = FMP_CHUNK_SIMPLE_KEY_VALUE
 		chunk.Key = uint64(payload[1])
-		chunk.Value = payload[2 : 2+valueLength]
-		chunk.Length = 2 + uint64(valueLength)
+		chunk.Value = payload[2:chunk.Length]
 
 	case 0x06:
 		valueLength := uint64(payload[2])
+		chunk.Length = 3 + valueLength
 		chunk.Type = FMP_CHUNK_SIMPLE_KEY_VALUE
 		chunk.Key = uint64(payload[1])
-		chunk.Value = payload[3 : 3+valueLength]
-		chunk.Length = 3 + uint64(valueLength)
+		chunk.Value = payload[3:chunk.Length]
 
 	case 0x07:
 		valueLength := parseVarUint64(payload[2 : 2+2])
-		payloadLimit := min(4+valueLength, uint64(len(payload)))
+		chunk.Length = min(4+valueLength, uint64(len(payload)))
 		chunk.Type = FMP_CHUNK_SEGMENTED_DATA
 		chunk.Index = uint64(payload[1])
-		chunk.Value = payload[4:payloadLimit]
-		chunk.Length = 4 + uint64(valueLength)
+		chunk.Value = payload[4:chunk.Length]
 
 	case 0x08:
-		chunk.Type = FMP_CHUNK_SIMPLE_DATA
-		chunk.Value = payload[1 : 1+2]
 		chunk.Length = 3
+		chunk.Type = FMP_CHUNK_SIMPLE_DATA
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x09:
+		chunk.Length = 4
 		chunk.Type = FMP_CHUNK_SIMPLE_KEY_VALUE
 		chunk.Key = parseVarUint64(payload[1 : 1+2])
-		chunk.Value = payload[3 : 3+1]
-		chunk.Length = 4
+		chunk.Value = payload[3:chunk.Length]
 
 	case 0x0A, 0x0B, 0x0C, 0x0D:
-		valueLength := uint64(2 * (payload[0] - 0x09))
+		valueLength := uint64(2 * (chunkCode - 0x09))
+		chunk.Length = 3 + valueLength
 		chunk.Type = FMP_CHUNK_SIMPLE_KEY_VALUE
 		chunk.Key = parseVarUint64(payload[1 : 1+2])
-		chunk.Value = payload[3 : 3+valueLength]
-		chunk.Length = 3 + uint64(valueLength)
+		chunk.Value = payload[3:chunk.Length]
 
 	case 0x0E:
 		if payload[1] == 0xFE {
-			chunk.Type = FMP_CHUNK_PATH_PUSH
-			chunk.Value = payload[1 : 1+8]
 			chunk.Length = 10
+			chunk.Type = FMP_CHUNK_PATH_PUSH
+			chunk.Value = payload[2:chunk.Length]
 			break
 		}
 
 		if payload[1] == 0xFF {
-			chunk.Type = FMP_CHUNK_SIMPLE_DATA
-			chunk.Value = payload[2 : 2+5]
 			chunk.Length = 7
+			chunk.Type = FMP_CHUNK_SIMPLE_DATA
+			chunk.Value = payload[2:chunk.Length]
 			break
 		}
 
 		valueLength := uint64(payload[2])
+		chunk.Length = 4 + valueLength
 		chunk.Type = FMP_CHUNK_SIMPLE_KEY_VALUE
 		chunk.Key = parseVarUint64(payload[1 : 1+2])
-		chunk.Value = payload[4 : 4+valueLength]
-		chunk.Length = 4 + uint64(valueLength)
+		chunk.Value = payload[4:chunk.Length]
 
 	case 0x0F:
 		valueLength := parseVarUint64(payload[3 : 3+2])
-		payloadLimit := min(5+valueLength, uint64(len(payload)))
+		chunk.Length = min(5+valueLength, uint64(len(payload)))
 		chunk.Type = FMP_CHUNK_SEGMENTED_DATA
 		chunk.Index = parseVarUint64(payload[1 : 1+2])
-		chunk.Value = payload[5:payloadLimit]
-		chunk.Length = 5 + valueLength
+		chunk.Value = payload[5:chunk.Length]
 
 	case 0x10, 0x11:
-		valueLength := 3 + (uint64(payload[0]) - 0x10)
+		valueLength := 3 + (uint64(chunkCode) - 0x10)
+		chunk.Length = 1 + valueLength
 		chunk.Type = FMP_CHUNK_SIMPLE_DATA
-		chunk.Value = payload[1 : 1+valueLength]
-		chunk.Length = 1 + uint64(valueLength)
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x12, 0x13, 0x14, 0x15:
-		valueLength := 1 + 2*(uint64(payload[0])-0x10)
+		valueLength := 1 + 2*(uint64(chunkCode)-0x10)
+		chunk.Length = 1 + valueLength
 		chunk.Type = FMP_CHUNK_SIMPLE_DATA
-		chunk.Value = payload[1 : 1+valueLength]
-		chunk.Length = 1 + uint64(valueLength)
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x16:
 		valueLength := uint64(payload[4])
 		chunk.Type = FMP_CHUNK_LONG_KEY_VALUE
+		chunk.Length = 5 + valueLength
 		chunk.Key = parseVarUint64(payload[1 : 1+3])
-		chunk.Value = payload[5 : 5+valueLength]
-		chunk.Length = 5 + uint64(valueLength)
+		chunk.Value = payload[5:chunk.Length]
 
 	case 0x17:
 		valueLength := parseVarUint64(payload[4 : 4+2])
+		chunk.Length = 6 + valueLength
 		chunk.Type = FMP_CHUNK_LONG_KEY_VALUE
 		chunk.Key = parseVarUint64(payload[1 : 1+3])
-		chunk.Value = payload[6 : 6+valueLength]
-		chunk.Length = 6 + uint64(valueLength)
+		chunk.Value = payload[6:chunk.Length]
 
 	case 0x19:
 		chunk.Type = FMP_CHUNK_SIMPLE_DATA
-		chunk.Value = payload[1 : 1+1]
 		chunk.Length = 2
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x1A, 0x1B, 0x1C, 0x1D:
-		valueLength := 2 * uint64(payload[0]-0x19)
-		chunk.Type = FMP_CHUNK_SIMPLE_DATA
-		chunk.Value = payload[1 : 1+valueLength]
+		valueLength := 2 * uint64(chunkCode-0x19)
 		chunk.Length = 1 + valueLength
+		chunk.Type = FMP_CHUNK_SIMPLE_DATA
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x1E:
 		keyLength := uint64(payload[1])
 		valueLength := uint64(payload[2+keyLength])
+		chunk.Length = 2 + keyLength + 1 + valueLength
 		chunk.Type = FMP_CHUNK_LONG_KEY_VALUE
 		chunk.Key = parseVarUint64(payload[2 : 2+keyLength])
-		chunk.Value = payload[2+keyLength+1 : 2+keyLength+1+valueLength]
-		chunk.Length = 2 + uint64(keyLength) + 1 + uint64(valueLength)
+		chunk.Value = payload[2+keyLength+1 : chunk.Length]
 
 	case 0x1F:
 		keyLength := uint64(uint64(payload[1]))
 		valueLength := parseVarUint64(payload[2+keyLength : 2+keyLength+2+1])
+		chunk.Length = 2 + keyLength + 2 + valueLength
 		chunk.Type = FMP_CHUNK_LONG_KEY_VALUE
 		chunk.Key = parseVarUint64(payload[2 : 2+keyLength])
-		chunk.Value = payload[2+keyLength+2 : 2+keyLength+2+valueLength]
-		chunk.Length = 2 + uint64(keyLength) + 2 + uint64(valueLength)
+		chunk.Value = payload[2+keyLength+2 : chunk.Length]
 
 	case 0x20:
 		if payload[1] == 0xFE {
-			chunk.Type = FMP_CHUNK_PATH_PUSH
-			chunk.Value = payload[1 : 1+8]
 			chunk.Length = 10
+			chunk.Type = FMP_CHUNK_PATH_PUSH
+			chunk.Value = payload[1:chunk.Length]
 			break
 		}
 
-		chunk.Type = FMP_CHUNK_PATH_PUSH
-		chunk.Value = payload[1 : 1+1]
 		chunk.Length = 2
+		chunk.Type = FMP_CHUNK_PATH_PUSH
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x23:
-		chunk.Type = FMP_CHUNK_SIMPLE_DATA
-		chunk.Value = payload[1 : 1+1]
 		chunk.Length = 2
+		chunk.Type = FMP_CHUNK_SIMPLE_DATA
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x28:
-		chunk.Type = FMP_CHUNK_PATH_PUSH
-		chunk.Value = payload[1 : 1+2]
 		chunk.Length = 3
+		chunk.Type = FMP_CHUNK_PATH_PUSH
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x30:
-		chunk.Type = FMP_CHUNK_PATH_PUSH
-		chunk.Value = payload[1 : 1+3]
 		chunk.Length = 4
+		chunk.Type = FMP_CHUNK_PATH_PUSH
+		chunk.Value = payload[1:chunk.Length]
 
 	case 0x38:
 		valueLength := uint64(payload[1])
+		chunk.Length = 2 + valueLength
 		chunk.Type = FMP_CHUNK_PATH_PUSH
-		chunk.Value = payload[2 : 2+valueLength]
-		chunk.Length = 2 + uint64(valueLength)
+		chunk.Value = payload[2:chunk.Length]
 
 	case 0x3D, 0x40:
 		chunk.Type = FMP_CHUNK_PATH_POP