The Samsung Slate 7 tablet has been one of the most popular devices for Windows 8 development since Microsoft gave BUILD 2011 attendees a Windows 8 version of the device. After that, people started to install Windows 8 previews on normal Windows 7 Samsung Slate 7 devices, mostly for development purposes.
Several updates have been made both by Microsoft and Samsung to ensure that all drivers and features work on the Windows 7 version of the slate. However, there have been a few issues popping up from time to time.
The latest I got was that when docking the tablet on the dock, the audio stopped working. Apparently this can also happen with the HDMI output. Fortunately, this is quite easy to fix. The issue is that when the tablet is docked, audio is routed to the dock audio port, which will work only if you have speakers attached. To solve the issue, you need to make sure the audio is not routed to the dock.
To change this just bring up the mixer control and select the audio destination you want. There are several ways to get to the mixer control in Windows. One of the easiest is to right-click on the speaker icon in the system tray and choose "Open Volume Mixer." The volume mixer window has a dropdown box under the device speaker icon that offers the choices you have for where the audio is directed.
You can find a long list of discussions and solutions for different issues with the device here. Make sure you have the latest Windows 8 updates downloaded and installed (do a quick restart of the tablet just to make sure) and also check out the Samsung Windows 8 preview drivers update if you are still experiencing issues.