As a work around, you could use VLC media player which includes a feature to artificially increase volume of a video to 200%
But why, when this simple fix will mean you can continue to watch content with loud volume within Windows Media Centre.
- In Windows, right click the speaker icon in the system tray, and select Playback Devices.
- Double click your default output device.
- Click the Enhancements tab.
- Tick the checkbox for Loudness Equalization.
- Click Ok to close, and return to the Desktop.
Finally, in Windows Media Centre, select Settings from the Tasks menu, then select TV / Audio and tick the checkbox for Auto Volume.
Note: VLC Media Player is great software, which is very useful when content is out of sync.