mshan wrote:re. Fusion
Will that volume control adjust the global Windows volume control (and thus should work with any Windows program)?
Typically, volume control messages from external devices which I assume the Antec volume control falls into, affect the master volume level of the sound card and not the volume of individual sound card components or application volume output levels. If your soundcard is hooked up to an amp via an S/PDif connection these volume controls may not have any affect on the level output to your amplifier; on my system the analogue output level is affected but the digital output is not, although the mute affects them both. This may vary between soundcards depending on how the drivers were designed or it may be the standard way to do it!
Media players with their own internal volume controls can affect the volume level sent over a digital output; this is because they can affect the signal level that is sent to the soundcard driver, rather than the level that is output from the driver. It is up to individual media applications to decide which volume that they affect; output to driver, sound card master volume, sound card WAVE output volume.
Devices such as keyboards and remote controls that can change & mute the volume as well as performing other multimedia functions usually do so by sending WM_APPCOMMAND messages. They are pre-defined Windows messaging features; not available in earlier versions of Windows.
These messages can be captured by a background utility and remapped so that they are sent to destinations that they otherwise wouldn’t reach.
Example: A media player can capture volume level messages from a remote control that were intended for the sound card master volume and remap them to control the output level from the application to the soundcard. The result of this is that your remote will now affect the volume sent over a digital output.
I know all this because I’ve written my own audio player application and wanted it to be able to respond to the multimedia keys on keyboards & remotes even when it doesn’t have focus. To do this I had to hijack the WM_APPCOMMAND messages and remap them; Windows Media Player is the only other application that I know of that does this.
This whole area needs tidying up within Windows and hopefully Vista will address this, not that I’m hopeful. As it is, I have to check that the application that has focus is not another media player that does actually require the WM_APPCOMMAND messages, before I hijack them. This means that I have to manually register which applications are multimedia players that are allowed access to the WM_APPCOMMAND messages.
This isn’t so much of an issue if you aren’t multi-tasking your media player applications, although on a HTPC system this is more likely.
I know it’s a bit of long answer, but I thought that some HTPC users might find it useful to have some background info in case they are having problems in this area.
)
).