For Media Center 20 or higher, use Setup wizard to setup a "Capture only" channel. You can also run Manage Channels tool and click Add button to add a channel. Select "Capture only" as channel type.
No additional configuration is needed for video capture devices in Media Center 20 or higher.
The following should be used only for earlier versions of Media Center.
How to configure audio for analog video capture / tuner devices that receive video / audio from line inputs
Analog tuner / capture devices usually have several video input lines. MC treats these as channels. Once setup, you can play video that is fed into one of these lines by double-clicking the input channel from the channels list.
Examples of these input lines are SVideo, Composite, Component/YRYBY. For example, you may have your cable TV set-top box connected to Composite, satellite TV box connected to YRYBY, and DVD player output connected to SVideo.
There are different audio input lines on the devices too, such as Line In, Aux In, Digital SPDIF.
Normally, each video line has a "related" audio line that MC will use if you do not make additional configuration. For example SVideo maybe associated to Line In, and Composite may be associated with Aux In. This will work for many users. However, if your audio is connected to a different input line (for example SPDIF), you need to configure it so MC will know which line to use.
This configuration is done via the property page of a device filter called "Video Crossbar". It can be accessed in two ways:
1. Via DirectShow filters list. While video is playing, right-click and go to "DirectShow filters" menu. Click crossbar filter in the list (for example "Hauppauge HD PVR Crossbar").
2. Via Configuration window. In standard TV view, click "TV Options..." button and choose "Settings...". In the resulting window, select the analog video device from the list under "Devices" and click the "Configure..." button. On the resulting window, choose "Advanced Properties" tab. Double-click "Video Crossbar...".
Once the crossbar property page is displayed, check the "Output" side (usually the right-hand side) first. The combo box should show "Video Decoder Out". Now check the Input side, the combo box should show the video line that you are trying to configure (or the video line you are currently watching). If it is not the line you try to configure, change it and click Apply. Next go back to "Output" side and select "Audio Decoder Out". Now the input side should show the current audio line. Change it to your desired line and click Apply and then OK (or click OK directly). That is it!
For MC17 (versions later that 17.0.23) only: If you have multiple video feeds, you should repeat the above procedure for each line (remember to click OK button after configuring a line because MC saves the info after the property page is dismissed).
For MC16 and earlier versions, only one audio line configuration is saved. You will need to reconfigure every time you change to a different video input channel.
Special notes on Hauppauge HD PVR and related devices:
These devices have capability of encoding audio in either AC3 format or AAC format. Only AC3 is supported in MC for now. If you still get no audio after the procedure described above, you should check "Hauppauge HD PVR Encoder" property page (accessed using right-click, "DirectShow Filters" menu). If it encodes to AAC, change it to AC3.