audio: fixed pcm exp cmds and removed buggy period negotiation

exp/pcm/resample/resample.go

@@ -81,9 +81,9 @@ func main() {
 	}
 
 	// Save resampled to file.
-	err = ioutil.WriteFile(outPath, resampled, 0644)
+	err = ioutil.WriteFile(outPath, resampled.Data, 0644)
 	if err != nil {
 		log.Fatal(err)
 	}
-	fmt.Println("Encoded and wrote", len(resampled), "bytes to file", outPath)
+	fmt.Println("Encoded and wrote", len(resampled.Data), "bytes to file", outPath)
 }

exp/pcm/stereo-to-mono/stereo-to-mono.go

@@ -77,9 +77,9 @@ func main() {
 	}
 
 	// Save mono to file.
-	err = ioutil.WriteFile(outPath, mono, 0644)
+	err = ioutil.WriteFile(outPath, mono.Data, 0644)
 	if err != nil {
 		log.Fatal(err)
 	}
-	fmt.Println("Encoded and wrote", len(mono), "bytes to file", outPath)
+	fmt.Println("Encoded and wrote", len(mono.Data), "bytes to file", outPath)
 }

input/audio/audio.go

@@ -284,17 +284,12 @@ func (d *Device) open() error {
 	// Some devices only accept even period sizes while others want powers of 2.
 	// So we will find the closest power of 2 to the desired period size.
 	const wantPeriod = 0.05 //seconds
-	secondSize := devRate * devChan * (devBits / 8)
-	wantPeriodSize := int(float64(secondSize) * wantPeriod)
+	bytesPerSecond := devRate * devChan * (devBits / 8)
+	wantPeriodSize := int(float64(bytesPerSecond) * wantPeriod)
 	nearWantPeriodSize := nearestPowerOfTwo(wantPeriodSize)
 
-	devPeriodSize, err := d.dev.NegotiatePeriodSize(nearWantPeriodSize)
-	if err != nil {
-		return err
-	}
-	d.l.Log(logger.Debug, pkg+"alsa device period size set", "periodsize", devPeriodSize)
-
-	devBufferSize, err := d.dev.NegotiateBufferSize(devPeriodSize * 2)
+	// At least two period sizes should fit within the buffer.
+	devBufferSize, err := d.dev.NegotiateBufferSize(nearWantPeriodSize * 2)
 	if err != nil {
 		return err
 	}