I have multiple friends that have their own home-theater-PC projects, so hopefully this may be of some use to them.
The Win32 multimedia timer services provide the greatest degree of timing accuracy. They allow you to schedule timing events at a higher resolution than other timer services. This can be useful in a multimedia application where timing accuracy is of utmost importance. For example, a MIDI application needs timing events that are as finely grained as possible.
Unfortunately, the Win32 multimedia timer is not part of the .NET Framework. However, by using the .NET interoperability services, the multimedia timer can be brought into the .NET fold.