Remove changes to reader for mono or stereo

This shouldn't be done in the library

reader.go

@@ -25,12 +25,7 @@ func NewReader(data []int16, channels int) *Reader {
 
 // Read implements the io.Reader interface
 func (r *Reader) Read(p []byte) (n int, err error) {
-	var samplesToRead int
-	if r.channels == 1 {
-		samplesToRead = len(p) / 4
-	} else {
-		samplesToRead = len(p) / 2
-	}
+	samplesToRead := len(p) / 2
 
 	if r.pos >= len(r.data) {
 		// Return EOF when there is no more data to read
@@ -42,24 +37,16 @@ func (r *Reader) Read(p []byte) (n int, err error) {
 	}
 
 	for i := 0; i < samplesToRead; i++ {
-		sample := r.data[r.pos]
-		if r.channels == 1 {
-			// Duplicate mono samples to stereo
-			p[i*4] = byte(sample & 0xFF)
-			p[i*4+1] = byte(sample >> 8)
-			p[i*4+2] = byte(sample & 0xFF)
-			p[i*4+3] = byte(sample >> 8)
-		} else {
-			// Assume stereo and copy directly
-			p[i*2] = byte(sample & 0xFF)
-			p[i*2+1] = byte(sample >> 8)
+		if r.pos >= len(r.data) {
+			return i * (4 / r.channels), io.EOF
 		}
+
+		sample := r.data[r.pos]
+		p[i*2] = byte(sample & 0xFF)
+		p[i*2+1] = byte(sample >> 8)
 		r.pos++
 	}
 
-	if r.channels == 1 {
-		return samplesToRead * 4, nil
-	}
 	return samplesToRead * 2, nil
 }
 
@@ -95,8 +82,3 @@ func (r *Reader) Seek(offset int64, whence int) (int64, error) {
 func (r *Reader) Position() int {
 	return r.pos
 }
-
-// SamplesRead returns the number of samples that have been read
-func (r *Reader) SamplesRead() int {
-	return r.pos / r.channels
-}