Win7 into the lock screen state, the computer does not sound how to repair

1, check the sound card, connectors, and speakers and other devices are connected to normal, anti-virus software to run anti-virus;

2, right click on "My Computer"----"Properties"---"Hardware"----"Device Manager", open the "sound, video and game controller" There is no problem, that is, to see if there is no yellow "" "If there is, reinstall the device driver to solve;

3, there is a sound but no small speakers, open the Control Panel----sound and video device----volume, in the "Put the volume icon into the taskbar" before the check mark;

4, no sound and no small speakers, open the Control Panel----Add and Remove Programs----Add delete Windows components, in the "accessories and tools" Before the check mark, click "Next", and then, shutdown restart, the system will be prompted to install new hardware, according to the prompts to install it;

5, uninstall the sound card driver, reinstall or upgrade the audio driver;

6, when the installation of sound card driver "can not find the AC chip" hint, there may be a computer poisoning, or because of illegal operation mistakenly deleted the sound card driver, or internal software conflict resolution is to reinstall the system and driver

7, simply ignore, shut down after waiting for a period of time and then reboot, sometimes sound problems will be resolved by themselves may you try

8. Start-Control Panel-sound and audio device-sound, see if it's tuned into a silent, then select Windows Default

9, click Start-Run, input regedit, enter, this opens the registry, point a few hkey-current-user, and then click on the ControlPanel items, and then hit the sound under its beep to change its value from No to Yes restart, is not again heard a long-lost switch machine voice.