You've given us no information about the make and model, operating system installed, laptop or desktop, or any of the steps you've already tried to fix the issue. Also, if you're using Windows 10, did the problem start occurring after the most recent April 2018 Update/Upgrade? The more information you give us, the better informed our answers will be.

In the meantime, regarding the sound, try these three things first:
1. Click on the speaker icon in the lower right corner and move the volume slider up.

2. RIGHT click on the same speaker icon, choose "Open Volume Mixer". Once that opens, make sure that none of the speaker icons at the bottom are muted. If so, click on them to unmute them.

3. Once again, RIGHT click on the speaker icon and choose "Open Sound Settings". Once that opens, look at the top line to make sure there is an "Output Device" listed. If there is or isn't one listed, then click on the "Troubleshoot" button to see if Windows can easily fix the issue.

Hope this helps and let us know more.

Grif