3. Click Playback devices.4. If you are using the Headset profile, select Bluetooth Hands-free Audio, and then click Set Default. Ifyou are using the AV profile, select Stereo Audio, and then click Set Default.5. Click OK.Performance problemsThis section provides solutions to performance-related problems of the computer.Excessive number of fragmented filesSolution: Use the Windows disk defragmentation or disk optimization feature to clean up the files.Note: Depending on the volume of the storage drives and amount of data stored on the storage drives, thedisk-defragmentation process might take up to several hours.1. Close any open programs and windows.2. Click the Start button to open the Start menu.3. Depending on your Windows version, do one of the following:• For Windows 7: Click Computer.• For Windows 10: Click File Explorer ➙ This PC.4. Right-click your C drive and then click Properties.5. Click the Tools tab.6. Depending on your Windows version, do one of the following:• For Windows 7: Click Defragment now.• For Windows 10: Click Optimize. Select the desired drive, and then click Optimize.7. Follow the instructions on the screen.Insufficient free storage drive spaceSolutions: Free up storage drive space.• Clean out your Inbox, Sent Items, and Deleted Items folders from your e-mail application.• Clean up your C drive.1. Click the Start button to open the Start menu.2. Depending on your Windows version, do one of the following:– For Windows 7: Click Computer.– For Windows 10: Click File Explorer ➙ This PC.3. Right-click your C drive and then click Properties.4. Check the amount of free space, and then click Disk Cleanup.5. A list of unnecessary file categories is displayed. Select each file category you want to delete,and then click OK.• Turn some Windows features off or remove some unnecessary programs.1. Depending on your Windows version, do one of the following:– For Windows 7: Click the Start button to open the Start menu.– For Windows 10: Right-click the Start button to open the Start context menu.2. Click Control Panel. View Control Panel using large icons or small icons, and then click Programsand Features.3. Do one of the following:Chapter 7. Troubleshooting, diagnostics, and recovery 69